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Experiment 1: Newton’s First Law

December 11, 2022/in Uncategorized /by SK

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Experiment 1: Newton’s First Law

Procedure Question:

Record your observations for each type of motion from Step 4 in the space below. Comment on where the water tended to move. If the water spilled, note which side it spilled from.

Questions:

Explain how your observations of the water demonstrate Newton’s law of inertia.

Draw a free body diagram of your box of water from the situation in Procedure 4d. Draw arrows for the force of gravity, the normal force (your hand pushing up on the box), and the stopping force (your hand decelerating the box as you stop.) What is the direction of the water’s acceleration?

*Note, free body diagrams are discussed in depth in Lab 2: Types of Forces. See Figure 3 for a sample diagram. Remember, the object is usually indicated as a box, and each force that acts upon the box is indicated with an arrow. The size of the arrow indicates the magnitude of the force, and the direction of the arrow indicates the direction which the force is acting. Each arrow should be labeled to identify the type of force. Note, not all objects have four forces acting upon them.

Ffriction

Fapp

Fnormal

Fgravity

Figure 3

Figure 3: Sample FBD

Can you think of an instance when you are driving or riding in a car that is similar to this experiment? Describe two instances where you feel forces in a car in terms of inertia.

Experiment 2: Unbalanced Forces – Newton’s Second Law

Table 1: Motion Data for Experiment 2

Trial	M1	M2	d of M2	Time (s)	Calculated Acceleration
Procedure 1
1
2
3
4
5
Average
Procedure 2
1
2
3
4
5
Average

Questions:

When you give one set of washers a downward push, does it move as easily as the other set? Does it stop before it reaches the floor? How do you explain this behavior?

Draw a FBD for M1 and M2 in each procedure (Procedure 1 and Procedure 2). Draw force arrows for the force due to gravity acting on both masses (Fg1 and Fg2), and the force of tension (FT). Also draw arrows indication the direction of acceleration, a.

Experiment 3: Newton’s Third Law

Questions:

Explain what caused the balloon to move in terms of Newton’s Third Law.

What is the force pair in this experiment? Draw a Free Body Diagram (FBD) to represent the (unbalanced) forces on the balloon/straw combination.

Add some mass to the straw by taping some metal washers to the bottom and repeat the experiment. How does this change the motion of the assembly? How does this change the FBD?

If the recoil of the rifle has the same magnitude force on the shooter as the rifle has on the bullet, why does the shooter not fly backwards with a high velocity?

Submit your document in a Word (.doc or .docx) or Rich Text Format (.rtf) for best compatibility.

Experiment 1: Newton’s First Law

Procedure Question:

Record your observations for each type of motion from Step 4 in the space below. Comment on where the water tended to move. If the water spilled, note which side it spilled from.

Questions:

Explain how your observations of the water demonstrate Newton’s law of inertia.

Ffriction

Fapp

Fnormal

Fgravity

Figure 3

Figure 3: Sample FBD

Can you think of an instance when you are driving or riding in a car that is similar to this experiment? Describe two instances where you feel forces in a car in terms of inertia.

Experiment 2: Unbalanced Forces – Newton’s Second Law

Table 1: Motion Data for Experiment 2

Trial	M1	M2	d of M2	Time (s)	Calculated Acceleration
Procedure 1
1
2
3
4
5
Average
Procedure 2
1
2
3
4
5
Average

Questions:

When you give one set of washers a downward push, does it move as easily as the other set? Does it stop before it reaches the floor? How do you explain this behavior?

Experiment 3: Newton’s Third Law

Questions:

Explain what caused the balloon to move in terms of Newton’s Third Law.

What is the force pair in this experiment? Draw a Free Body Diagram (FBD) to represent the (unbalanced) forces on the balloon/straw combination.

Add some mass to the straw by taping some metal washers to the bottom and repeat the experiment. How does this change the motion of the assembly? How does this change the FBD?

If the recoil of the rifle has the same magnitude force on the shooter as the rifle has on the bullet, why does the shooter not fly backwards with a high velocity?

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Workplace Hazard Analysis and Review of Associated Risk

December 11, 2022/in Uncategorized /by SK

OSH 366 Hazard Identification and Control

Week 3: Chapter 2

Workplace Hazard Analysis and Review of Associated Risk

2.0 Learning Goals

Identify the use of audits and inspections

Use the tools to gather information and analyze for the workplace review

Define the roles played by outside specialists, Spvrs, Ee’s

Identify sources for risk and hazard data

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.1 Analysis of the Workplace

The starting point in analysis and evaluation development is to consider workplace as a system of cause and effect with inherent risk built into the work environment.

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.1 Analysis of the Workplace

Steps to select the methods or tools that can be used to identify and analyze the work environment include:

Review current job descriptions and protocols for employee tasks…. (this includes interviews)

Performing specific task analysis taking into consideration hazards and associated risk

Utilizing workplace surveys based on existing standards, procedures, regulations or guidelines that have been customized and tested for consistency

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.1 Analysis of the Workplace

Utilizing change analysis of planned, new, modified or relocated facilities, processes, materials and equipment to update procedures and/or guidelines

Utilizing walk-around inspections conducted by knowledgeable Ee’s

Reviewing documentation of the history of similar industries past work experiences.

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.1 Analysis of the Workplace

NOTE:

Site analysis has important elements that are critical for an effective overview:

Analysis should cover all areas of the workplace

Analysis should be conducted at regular intervals.. Frequency will depend on the size of the workplace and the potential hazards and severity of risks.

Ee’s should be trained on hazard recognition/risk and expand the hazard inventory to update JHA.

OSH 366 W2 PPT2 Organizational Roles and JHA’s

Conduct Comprehensive

Baseline survey

Identify hazards

Develop/update hazards inventories

Develop/Update controls

Conduct periodic surveys

Figure 2-1 Overview of a Comprehensive Baseline Review

Let’s now turn to the Job Hazard Analysis. What is a JHA? As stated before, it is a “management tool” used to anticipate and assess the existing and potential hazards of a job, to understand the consequences of the risk, and to act as an aid in helping identify, eliminate, or control hazards. So the bottom line is that the JHA is a tool that focuses on the relationship between the employee; the job as a whole unit; the steps that make up the job; the tasks that are defined in each step; the tools, materials and equipment being used; Existing and potential hazards; the consequences of exposure to those hazards; potential at-risk events associated with each task; existing policies and procedures; and the nature of the physical environment that the job is completed within.

Thus, the assessing of all of the components of a task, a comprehensive overview is developed that allows one to focus on the essential areas where change may be needed.

Now let us begin with reviewing the individual steps in the JHA process found as Figure 2-1 in the text. This is the preplanning stage. Again, JHA’s are concerned with identification and the controlling hazards.

The JHA process involves 5 steps… JHA always begins with:

Step 1. Conducting a comprehensive baseline survey.

A comprehensive baseline survey means first identifying all occupations and job tasks by occupation/position and evaluate them for existing and potential hazards. Yes, this does mean every job title such as maintenance workers, painters, electricians and even laborers etc. and all the tasks involved that employee is required to perform.

To make the baseline survey process more meaningful and save on your time, focus your efforts on identifying the “critical tasks” for each job. “Critical tasks” are those in which there is potential to produce major loss to people, property, process and/or environment when not performed properly. For example a critical task could be emergency shut down actions for specific equipment, a control room operator’s procedures for instrumentation loss or donning of escape breathing apparatus. Remember most accidents occur in a work area to which a worker is not accustomed and during a task that a worker’s unusual task.

Be mindful that sometimes-occupational titles maybe generic in nature and the worker may or may not be performing tasks you think they are performing.

Step 2. Identify all the hazards that are critical for each job title or task. These means both safety and health hazards and inventory them. Inventories of hazards are important in that they will assist the safety professional to keep an accurate account of all the hazards that they are aware. Be aware this list of hazards for each job and specific tasks may grow over time. Inventories are important, as they will keep track of what works and what doesn’t.

Step 3. You are then to develop or update controls and inventory them. Once hazards are identified you are responsible for designing and implementing controls. Remember controls have a specific order to be followed:

1.Design/Engineering Controls

2. Administrative Controls

3. PPE

Step 4. Once controls are implemented they must be periodically checked for effectiveness. Think of this as a quality assurance check. At this point as a safety professional you are doing things such as questioning employees about the hazards and the controls, performing monitoring, etc.

JHA’s are a continuous cycle used to control hazards in the workplace. A review of workplace hazards is a systematic cause and effect relationship approach with an evaluation of risk built into the work environment. You must evaluate both the hazard and the risk of the hazard to cause harm. Risk assessments is defined as a chance or loss or gain a measure of potential loss that considers both the magnitude of a loss and its likelihood of occurring and it uses a process used to identify, quantify or rank risk. Organizations should consider that even adequate controls have been put into place there will be residual risks. Safety professionals are to reduce the level of risk to within acceptable levels. Residual risk is the level of risk remaining after all risk control measure has been implemented.

Specific tools used to identify and analyze the work environment hazards, which include:

Reviewing job descriptions and specific tasks workers must complete

Performing specific job analysis, taking consideration of hazards and risks

Utilizing workplace surveys based on existing standards, procedures, regulations or guidelines that are uniform

Utilizing change analysis

Walk around inspections

Similar industry research

One of the most important issues when being confronted with implementing a job safety analysis program is which jobs do we do first. Is it the jobs that are the highest paying jobs, the jobs that are historically the most risky jobs, or do we just start at one end of the plant and go through it job by job. Well, my recommendation, and the recommendation of OSHA is that you establish a priority list. At the top of the list should be the following jobs:

jobs with the highest injury or illness rates;

jobs with the potential to cause severe or disabling injuries or illnesses, even if there is no history of previous accidents;

jobs in which one simple human error could lead to a severe accident or injury;

jobs that are new to your operation or have undergone changes in processes and procedures; and

jobs complex enough to require written instructions.

So, how do we begin. Well, OSHA recommends the following steps.

First, Involve your employees. Your employees have a unique understanding of the jobs they do. This knowledge can be invaluable when trying to determine what hazards are associated with the job. What may look extremely easy when watching an employee work may in actuality be very difficult and strenuous. Involving employees in creating the job steps and determining the hazards associated with those job steps will help avoid oversights, ensure quality analysis, and help obtain worker “buy-in” to the process and solutions. They will share in the ownership of the JHA and will be less willing to deny knowledge of the hazards associated with the job and less willing to avoid following the safety protocol designed by you and the employee.

Second, Review the accident history. Reviewing on your own and with your employees the accident history of the job being examined, as well as the company history will also help with buy-in and help in determining which jobs should receive priority in having a JHA done on that job first. In addition, determining or reviewing “near misses” on that job is important in designing the JHA for that job. Near misses are those situations where an accident didn’t happen but could have or nearly resulted in an injury or death. These near misses are indicators that the existing hazard controls (if any) may not be adequate and certainly deserve a closer examination.

Third, conduct a preliminary job review. This is where you want to discuss with your employees the hazards that they know exist in their job(s). You should also brainstorm with them for ideas on how to eliminate or control those hazards. Of course, if an employee points out some hazard that poses an immediate danger to the employees life or health, you should take immediate action to eliminate the hazard to protect the worker. Do not wait to complete your JHA.

Fourth, List, rank and set priorities for hazardous jobs. List those jobs that present the most unacceptable hazards, whether they be physical or environmental hazards. Check off the ones that are most likely to occur and the ones with the most severe consequences. These jobs should get your second highest priority, next to those the present an immediate danger to life or health.

Fifth, Outline the steps or tasks.

So, we have our pre-planning stages above, but here is where we actually start the formal process of a JHA – that is, breaking down a job to its individual components, or job tasks or what we prefer to call job STEPS. When beginning a JHA, watch the employee perform the job and list each step as the worker takes it. Be sure to record enough information to describe each step without getting overly detailed. Avoid making the breakdown of steps so detailed that it becomes unnecessarily long or so broad that it does not include basic steps. Of course, you should have the employee who performs the job review your listing of steps and see if you can combines some outlined steps into one or if you need to break them apart because they require separate tasks or key physical efforts. Remember, when you talk to the employee make sure they understand that you are evaluating the job, not their job performance. You may also want to video-tape the employee while they are performing the job. These visual recordings can certainly help when an employee is performing complex tasks or doing the steps fairly quickly.

As your text points out, JHA’s are not stand alone processes or procedures. They must be done in conjunction with your other safety programs and policies. For example, how does this fit within your employee handbook, or union contract? Are employees encouraged to report safety hazards and how is this reporting accomplished? In Appendix B of your textbook, a sample form for reporting hazards can be found. Of course, you can design your own form using this as a template or suggestion. How can you improve these means of communications? If this information is reported, are employee concerns being addressed quickly enough or just ignored? Do work orders get generated from these reports and are they acted upon in a timely manner. If not, are employees informed of any holdup or are they left with the impression that this is just another safety program or joke of the month? Are these reports of hazard tracked and by what means? Are they complied and then used in future JHA’s or used to revise existing JHA’s? Answers to all of these questions will greatly impact your organizations actual and perceived commitment to safety and health. A breakdown in any one of these components can negatively impact your overall success.

Modes of Workplace Analysis

There are several modes (techniques) of workplace analysis safety departments or safety directors can utilize. They include:

Inspections and audits

Checklists

Use of consultants and Outside specialists

Ee’ Interviews

OSH 366 W2 PPT2 Organizational Roles and JHA’s

Inspections and Audits

Inspections and audits are two important and most frequent aspects of an effective workplace analysis in development of a JHA.

Inspections are “tactics” generally “walk-around” to identify conditions that do not comply with defined safety procedures and requirements (time consuming)

Audits are a “strategy” that attempts to program status by assigning numerical value to program elements.

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.3 Checklists

Checklists are often developed from negative experiences, where system failed or unidentified hazards resulted in injuries or other loss-producing events.

Beware of generic checklists

Modify checklist to be site specific

See Appendix E for sample checklist

OSH 366 W2 PPT2 Organizational Roles and JHA’s

Appendix E E.1 SELF INSPECTION CHECKLIST

Employer Postings	Yes	No
Is the required OSHA workplace poster displayed in a prominent location where all employees are likely to see it?
Are emergency telephone numbers posted where they can be readily found in case of emergency?
Where employees may be exposed to any toxic substances or harmful agents, has appropriate information concerning employee access to medical and exposure records and MSD Sheets been posted or otherwise made readily available to affected employees?
Are signs concerning egress from buildings, room capacities, floor loading, biohazards, exposures to x-ray, microwave, or other harmful radiation or substances posted where appropriate?

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.3.1 Consultants and Outside Specialists

Outside services may be necessary for safety departments and safety directors who lack specific knowledge in an area such as:

Engineers

Workers compensation specialists

Consulting Services

Environmental Sciences

Industrial Hygienist

OSH 366 W2 PPT2 Organizational Roles and JHA’s

Industrial Hygienists

Industrial hygiene is generally defined as the art and science dedicated to the anticipation, recognition, evaluation, communication and control of environmental stressors in, or arising from, the work place that may result in injury, illness, impairment, or affect the well being of workers and members of the community.

These stressors are divided into the categories biological, chemical, physical, ergonomic and psychosocial.

IH testing includes air, dust, vapors, noise, etc.

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.3.2 Employee Interviews

Often overlooked mode of hazard identification include employee interviews. Forms of interviews include:

One-on-one interviews

Informal conversations with Ee’s

Voluntary anonymous surveys

Note: See General Guidelines that can be used when conducting Ee’ interviews pg. 44

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.4 Types of Inspections

There are many types of inspections that can be performed which include:

General walk-around inspections

Verification reviews (Fig. 2-2)

Focus Reviews

Self-Assessment

Document Review

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.4.1 General Walk-around Inspections

Walk-around inspections are used to conduct periodic and daily inspections of the workplace. They identify obvious blatant hazards and visible at-risk events.

Mgrs and Supvrs should conduct routine walk-around inspections

Safety committee members as well

OSH 366 W2 PPT2 Organizational Roles and JHA’s

Table 2-1 Important Elements of Site Reviews

Important elements of regular site reviews and show how critical follow-up reviews are to the process.

Reviews should cover all areas of the workplace, targeting high-hazard operations

Reviews should be conducted at regular intervals. The frequency will depend on the size of the workplace and the nature of the risks and hazards

Use JHA’s to review the steps and tasks that are being completed and ensure that the correct tools, equipment, materials, etc. are in use

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.4.2 Verification Reviews

Items identified from walk-around inspections must be reviewed for appropriate completion.

Avoid “pencil whipping”

OSH 366 W2 PPT2 Organizational Roles and JHA’s

Analyze work

Define subsystems

Identify

Hazards

Define ongoing haz. situations

Determine haz. events

Analyze harm or exposure

Estimate risk

Is risk tolerable

Introduce corrective/action

No change necessary monitor results

Verify

Yes

Fig. 2-2 Flow Diagram of the Risk Toolkit

2.4.3 Focus Reviews

Narrows the scope of a inspection to one process or audit component that needs greater assistance in implementing a sustainable hazard control.

JHA are used to target jobs and tasks where the hazards of specific actions or elements pose the greatest threat

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.4.5 Document Review

Document and records are to be inspected to verify that what you said you would do that you did. All documents should be properly completed, stored and secured. Documents to be reviewed.

Policy statements

Training

Procedures

Recordkeeping

JHA’s

NOTE: Keep all document filed both electronically and hard copies

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.4.6 Written Inspection Reports

Necessary to record hazards identified, responsible person for corrective action and tracking of hazards to completion.

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.5 Who should Review the workplace

Everyone is responsible for actively reviewing the workplace. However Ee’s with specific skills and perspectives should be involved in reviewing the workplace.

Each level of employee should have specific responsibilities based on their authority and responsibility.

OSH 366 W2 PPT2 Organizational Roles and JHA’s

Management Workplace Inspections/JHA Role

Management must:

Identify hazards in the workplace that could result in injury or illness

Evaluate the level of risk to help determine what controls to implement

Select an appropriate solution to control the hazard and/or protect

the employee.

OSH 366 W2 PPT2 Organizational Roles and JHA’s

We have discussed a lot information concerning the importance of JHA and value to the organization, steps to perform a JHA now we will turn our attention the organizational roles impacting JHA success. Each level of employee within the organization plays a role in JHA success. For the purposes of this course employee also refers to management.

Lets start with management:

Management must:

Identify hazards in the workplace that could result in injury or illness

Evaluate the level of risk to help determine what controls to implement

Select an appropriate solution to control the hazard and/or protect

the employee.

Management should establish a hazard reporting initiative which is executed by supervisors. A hazard reporting initiative is basically creating a system for worker to feel comfortable to report hazards to management so they can be fixed.

A good hazard reporting initiative includes management should receive feedback from both supervisors and employees on the control of risk and hazards because of:

Budget Resources

Set Program standards

Set objectives related to inspections

Management Workplace Inspections/JHA Role

A good hazard reporting initiative includes management should receive feedback from both supervisors and employees on the control of risk and hazards because of:

Budget Resources

Set Program standards

Set objectives related to inspections

OSH 366 W2 PPT2 Organizational Roles and JHA’s

Lets start with management:

Management must:

Identify hazards in the workplace that could result in injury or illness

Evaluate the level of risk to help determine what controls to implement

Select an appropriate solution to control the hazard and/or protect

the employee.

A good hazard reporting initiative includes management should receive feedback from both supervisors and employees on the control of risk and hazards because of:

Budget Resources

Set Program standards

Set objectives related to inspections

Supervisors Workplace Inspections/JHA Role

Supervisors must review all work areas for hazards (perform inspections and audits) and hazards identified and reported by employees should be reported to supervisors:

Supervisors should encourage employees to report hazards document and track them

Supervisors should be attempt to control hazards which they can

Complete inspections of workplaces

Be involved in audits

OSH 366 W2 PPT2 Organizational Roles and JHA’s

Supervisors must review all work areas for hazards (perform inspections and audits) and hazards identified and reported by employees should be reported to supervisors:

Supervisors should encourage employees to report hazards document and track them

Supervisors should be attempt to control hazards which they can

Complete inspections of workplaces

Be involved in audits

Supervisor Obstacles to Inspections and Audits

OSH 366 W2 PPT2 Organizational Roles and JHA’s

These include:

Fear of losing their job

No money available for needed changes identified during the hazard identification

There is a risk in spending money for safety

The “what’s in it for me?” attitude

Many employees want to change but are afraid to take responsibility for it

No support from upper Management

No time or follow-through from top Management

Make it work or “can do attitude

James Rougthon and James Mercurio book Developing an Effective Safety Culture they have identified several obstacles which causes supervisors to neglect to perform inspection and auditing duties.

These include:

Fear of losing their job

No money available for needed changes identified during the hazard identification

There is a risk in spending money for safety

The “what’s in it for me?” attitude

Many employees want to change but are afraid to take responsibility for it

No support from upper Management

No time or follow-through from top Management

Make it work or “can do attitude

Employees Workplace Inspections/JHA Role

Employees play a role in the JHA process. Employees must understand hazard analysis is a work requirement

Employees need to be involved in hazard analysis from the beginning so:

The process that is taking place is better understood

The value of a change is seen by the employee

OSH 366 W2 PPT2 Organizational Roles and JHA’s

Employees play a role in the JHA process. Employees must understand hazard analysis is a work requirement

Employees need to be involved in hazard analysis from the beginning so:

The process that is taking place is better understood

The value of a change is seen by the employee

Employee Obstacles to Successful Inspection and Auditing

OSH 366 W2 PPT2 Organizational Roles and JHA’s

Obstacles which causes employees to neglect to perform inspection and auditing duties. These include:

Fear and a lack of trust

Supervisors not willing to listen and support

Communication is one way (top-down)

Organization is not alignment on safety; production is number one at the line level

Supervisors not willing to hear problems and receive feedback

Intimidation

People not willing to take personal responsibility; too easy to shift blame

Lack of consistency and follow-through, past efforts fade away

Obstacles which causes employees to neglect to perform inspection and auditing duties. These include:

Fear and a lack of trust

Supervisors not willing to listen and support

Communication is one way (top-down)

Organization is not alignment on safety; production is number one at the line level

Supervisors not willing to hear problems and receive feedback

Intimidation

People not willing to take personal responsibility; too easy to shift blame

Lack of consistency and follow-through, past efforts fade away

2.5.3 Safety Professionals

Safety professionals can act as a mentor and provide guidance on methods to conduct inspection.

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.6 Preventive Maintenance

Preventive maintenance (PM) has a direct relationship with safety performance. Good PM programs plays a major role in ensuring that hazard controls continues by:

Keeping new hazards from occurring due to equipment malfunction or product defect

Target areas of potential high risk

Review maintenance records for proper PM

Poor housekeeping and maintenance are direct indicators’ of poor PM

OSH 366 W2 PPT2 Organizational Roles and JHA’s

Safety Committees

Joint labor-management committees or a safety committee are popular methods of increasing employee participation in workplace inspections.

If a safety committee is to part of a JHA or participates in hazard identification be certain they are adequately trained and they are to assist in the correction of hazards.

OSH 366 W2 PPT2 Organizational Roles and JHA’s

Joint labor-management committees or a safety committee are popular methods of increasing employee participation in JHA’s. Safety committees come in various sizes and differing responsibilities such as incidents and accident investigations, administering workplace surveys or participating or JHA’s. If a safety committee is to part of a JHA or participates in hazard identification be certain they are adequately trained and they are to assist in the correction of hazards.

2.7 Other things to consider

Retroactive analysis tools that assist in ensuring controls stay in place and new hazards do not appear include data collection and analysis of:

Incident investigations

Injury and illness trend analysis

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.7 Incident Investigations

Incident investigations are used to identify and uncover hazards that were missed of created when a process or operation has slipped out of control.

Gather information on near-misses

OSH 366 W2 PPT2 Organizational Roles and JHA’s

2.7.2. Trend Analysis

The analysis of trends over time for the determination of the effectiveness of your safety processes. Are you losses decreasing? Items to review for trend analysis include:

Injury and illness records (OSHA 300 Logs)

First Aid Reports

OSH 366 W2 PPT2 Organizational Roles and JHA’s

Romantic Facts

December 11, 2022/in Uncategorized /by SK

Can someone please help with these discussions please?

Week 9-

“Chapters 24 and 25”

For your primary post, provide a link to a current news article or science article that is related to at least one topic from Chapter 24 “Oceans, Atmosphere & Climatic Effects” and/or Chapter 25 “Driving Forces of Weather.”

In addition to the link, write a paragraph of at least 125 words describing the article and how it relates to the material from the textbook. Which concepts from the text does it mention, cover or depend on? Is the article more or less detailed on the science than the textbook?

Make a substantive reply to at least one fellow student.

Week 10-

“Chapters 26 and 27”

For your primary post, provide a link to a current news article or science article that is related to at least one topic from Chapter 26 “Solar System” and/or Chapter 27 “Stars & Galaxies.”

Make a substantive reply to at least one fellow student.

Week 11-

“Romantic Facts”

“Reality provides us with fact so romantic that imagination itself could add nothing to them” — Jules Verne

Respond to the above quote.

Do you agree or disagree?
What field did you explore in this class, that makes this true? Why?
What field did you explore that indicates this couldn’t be further from the truth? Why?

Chapter 24: The Oceans, Atmosphere, and Climatic Effects

© 2017 Pearson Education, Inc.

Chapter 24 Lecture

1

This lecture will help you understand:

Earth’s Atmosphere and Oceans

Components of Earth’s Oceans

Ocean Waves, Tides, and Shorelines

Components of Earth’s Atmosphere

Solar Energy

Driving Forces of Air Motion

Global Circulation Patterns

© 2017 Pearson Education, Inc.

2

Earth’s Atmosphere and Oceans

Seventy-one percent of Earth’s surface is covered by water.

Water’s high specific heat capacity accounts for moderate temperatures in coastal lands.

© 2017 Pearson Education, Inc.

3

Earth’s Atmosphere and Oceans

Earth’s early atmosphere appeared before the Sun was fully formed.

Hydrogen

Helium

The Sun’s formation swept away Earth’s original atmosphere and a new atmosphere formed.

© 2017 Pearson Education, Inc.

4

Earth’s Atmosphere and Oceans

Earth’s atmosphere developed in stages:

Hot gases escaped through volcanoes and fissures.

Free oxygen occurred as a result of photosynthesis by cyanobacteria.

Ozone began to accumulate in the upper atmosphere.

Water vapor condensed to form oceans.

© 2017 Pearson Education, Inc.

Components of Earth’s Oceans: The Ocean Floor

The ocean floor encompasses continental margins and deep ocean basins.

© 2017 Pearson Education, Inc.

6

Components of Earth’s Oceans: The Ocean Floor

Continental margins are between shorelines and deep ocean basins.

Continental shelf—shallow, underwater extension of the continent.

Continental slope—marks boundary between continental and oceanic crust.

Continental rise—wedge of accumulated sediment at base of continental slope.

© 2017 Pearson Education, Inc.

7

Components of Earth’s Oceans: The Ocean Floor

The ocean bottom is etched with deep canyons, trenches, and crevasses.

Underwater mountains rise upward from the seafloor.

The deep-ocean basin:

Basalt from seafloor spreading plus thick accumulations of sediment

Abyssal plains, ocean trenches, and seamounts

© 2017 Pearson Education, Inc.

8

Components of Earth’s Oceans: The Ocean Floor

The deep-ocean basin:

Abyssal plains—flattest part of the ocean floor due to accumulated sediment

Ocean trenches—long, deep, steep troughs at subduction zones

Seamounts—elevated seafloor from volcanism

Mid-ocean ridges:

Sites of seafloor spreading (volcanic and tectonic activity)

A global mid-ocean ridge system winds all around the Earth

© 2017 Pearson Education, Inc.

9

Components of Earth’s Oceans: The Ocean Floor

The deepest parts of the ocean are at the ocean trenches near some of the continents.

The shallowest waters are in the middle of the oceans around underwater mountains (mid-ocean ridge system).

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Ocean trenches are the deepest parts of the ocean floor because

that is where oceanic crust meets continental crust.

that is where subduction occurs.

no sediment accumulates in trenches.

all accumulated sediment settles in the abyssal plain.

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Components of Earth’s Oceans CHECK YOUR NEIGHBOR

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B. that is where subduction occurs.

Ocean trenches are the deepest parts of the ocean floor because

that is where oceanic crust meets continental crust.

that is where subduction occurs.

no sediment accumulates in trenches.

all accumulated sediment settles in the abyssal plain.

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Components of Earth’s Oceans CHECK YOUR ANSWER

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B. that is where subduction occurs.

Oceanic crust does meet continental crust at deep ocean trenches, but these plate boundaries do not all have deep trenches.

C. and D. sediment does accumulate in the trenches.

Ocean Waves, Tides, and Shorelines

Characteristics of waves—waves get their energy from the wind.

The crest is the peak of the wave.

The trough is the low area between waves.

Wave height is the distance between a trough and a crest.

Wavelength is the horizontal distance between crests.

Wave period is the time interval between the passage of two successive crests.

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Ocean Waves, Tides, and Shorelines

Height, length, and period of a wave depend on:

Wind speed

Length of time wind has blown

Fetch—the distance that the wind has traveled across open water

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Ocean Waves, Tides, and Shorelines

Waves on the ocean surface are orbital waves.

Wave energy moves forward: the disturbance moves, not the water.

Occurs in the open sea in deep water.

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Ocean Waves, Tides, and Shorelines

Waves at the shoreline:

In shallow water, at a depth of about one-half the wavelength, the wave begins to “feel bottom”

The wave grows higher as it slows and wavelength shortens

As a steep wave front collapses, the wave breaks

The turbulent water created by the crash is called surf

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When a wave approaches the shore, the water depth decreases. This affects the wave by flattening its circular motion,

decreasing its speed, and increasing distance between waves and wave height.

increasing its speed and distance between waves, and decreasing wave period.

decreasing its speed and distance between waves, causing wave height to increase.

increasing its speed and distance between waves, causing wave height to increase.

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Ocean Waves, Tides, and Shorelines CHECK YOUR NEIGHBOR

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C. decreasing its speed and distance between waves, causing wave height to increase.

When a wave approaches the shore, the water depth decreases. This affects the wave by flattening its circular motion,

decreasing its speed, and increasing distance between waves and wave height.

increasing its speed and distance between waves, and decreasing wave period.

decreasing its speed and distance between waves, causing wave height to increase.

increasing its speed and distance between waves, causing wave height to increase.

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Ocean Waves, Tides, and Shorelines CHECK YOUR ANSWER

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C. decreasing its speed and distance between waves, causing wave height to increase.

Ocean Waves, Tides, and Shorelines: Wave Refraction

As waves enter shallow water:

Forward direction changes.

Wave nearest to shore slows and lags behind incoming waves.

The incoming waves also slow and begin to pivot.

As this continues the wave crest bends and pivots around the slower portion of the wave—wave refraction.

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Ocean Waves, Tides, and Shorelines: Wave Refraction

Longshore Current:

The oblique approach of waves—flow is parallel to the shore.

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Ocean Waves, Tides, and Shorelines: Wave Refraction

Impact of wave refraction on shorelines:

Wave energy unevenly distributed

Concentrated in headland areas—area of erosion

Diluted in adjacent coves and bays—area of deposition

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Ocean Waves, Tides, and Shorelines: The Work of Ocean Waves

Characteristic coastal erosional landforms:

Wave cut platform

Sea cliff

Sea cave

Sea arch

Sea stack

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Ocean Waves, Tides, and Shorelines: The Work of Ocean Waves

Characteristic coastal depositional landforms:

Beach

Spit

Lagoon

Barrier island

Inlet

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Ocean Waves, Tides, and Shorelines

Coral reefs are composed of actively growing coral organisms.

Organisms secrete calcium carbonate as they grow—that is what we see.

Many reefs survive on photosynthetic algae.

Coral bleaching is an indicator of global warming.

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Ocean Waves, Tides, and Shorelines: Link to Physics: Ocean Tides

Tides occur because of the differences in the gravitational pull exerted by the Moon on opposite sides of Earth.

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Ocean Waves, Tides, and Shorelines: Link to Physics: Ocean Tides

Because Earth spins on its axis once a day, it should have two distinct tides 12 hours apart.

But because the Moon moves around Earth, the times of the tides vary each day.

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Ocean Waves, Tides, and Shorelines: Link to Physics: Ocean Tides

Alignment of the Sun, Earth, and Moon causes spring tides—more dramatic highs and lows.

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Ocean Waves, Tides, and Shorelines: Link to Physics: Ocean Tides

When the pull of the Sun and Moon are perpendicular to each other, we get neap tides—the highs not as high, and the lows not as low.

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Components of Earth’s Atmosphere

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Components of Earth’s Atmosphere

Earth’s atmosphere is divided into layers, each with different characteristics:

Troposphere

Stratosphere

Mesosphere

Thermosphere

Ionosphere

Exosphere

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Components of Earth’s Atmosphere

Troposphere:

Lowest and thinnest layer

16 km at equator, 8 km at poles

90% of the atmosphere’s mass

Where weather occurs

Water vapor and clouds

Temperature decreases with altitude

6ºC per kilometer

Top of troposphere averages –50ºC

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Components of Earth’s Atmosphere

Stratosphere:

Top of troposphere to 50 km above surface

Ozone layer

Absorbs harmful UV radiation

Temperature increases because of ozone absorption of UV radiation.

Ranges from –50ºC at base to 0ºC at top

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Components of Earth’s Atmosphere

Mesosphere:

Extends from stratosphere to altitude of 80 km

Temperature decreases with altitude

Gases in this layer absorb very little UV radiation.

0ºC at bottom to –90ºC at top

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Components of Earth’s Atmosphere

Thermosphere:

Temperature increases with altitude

Temperature is related to average speed of gas molecules—very high speed gives high temperatures

Temperatures up to 1500ºC

Very low density of gas molecules means very little heat absorption—it would feel cold.

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Components of Earth’s Atmosphere

Ionosphere:

Electrified region within the thermosphere and upper mesosphere

Auroras: fiery displays of light near Earth’s magnetic poles

Exosphere:

The interface between Earth and space

Beyond 500 km, atoms and molecules can escape to space

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Components of Earth’s Atmosphere

The average temperature of Earth’s atmosphere varies in a zig-zag pattern with altitude.

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Solar Energy

Solar radiation is electromagnetic energy emitted by the Sun.

Visible, short-wavelength radiation

Terrestrial radiation is reemitted solar radiation from Earth’s surface.

Infrared, longer-wavelength radiation

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Solar Energy

The Sun warms Earth’s ground, and the ground, in turn, warms Earth’s atmosphere.

Earth’s temperature varies according to the degree of solar intensity—the amount of solar radiation per area.

Where solar intensity is higher, temperatures are higher.

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Solar Energy

Solar intensity is highest where the Sun’s rays strike Earth’s surface straight on.

Flashlight beam at 90º angle to the surface

Equatorial regions

Solar intensity is weaker where the Sun’s rays strike Earth’s surface at an angle.

Flashlight beam at an angle

Higher latitudes

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Solar Energy

Variation in solar intensity with latitude and the tilt of the Earth’s axis helps to explain the different seasons.

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Solar Energy

When the Sun’s rays are closest to perpendicular at any spot on the Earth, that region’s season is summer.

Six months later, as the rays fall upon the same region more obliquely, the season is winter.

In between are the seasons fall and spring.

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Solar Energy: The Greenhouse Effect and Global Warming

Human activities pump greenhouse gases into the atmosphere: carbon dioxide, methane, nitrous oxide, ozone, CFCs.

The result is a warming Earth.

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Driving Forces of Air Motion

Underlying Driving Force:

Unequal heating of Earth’s surface

Atmospheric pressure:

Force the atmosphere exerts on a surface area

At any level in the atmosphere, force = total weight of air above that level.

At higher elevations, with fewer air molecules above the atmospheric pressure is less.

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Convection Cycle:

Warm air parcel rises; Cooler air parcel sinks

Warm air is less dense than cool air

Convection currents stir the wind:

Wind is air that flows horizontally from higher pressure to lower pressure.

The greater the pressure gradient, the stronger the wind.

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Driving Forces of Air Motion: Temperature-Pressure Relationship

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Driving Forces of Air Motion: Temperature-Pressure Relationship

Pressure differences are caused by uneven heating of the Earth’s surface.

Local differences in heating contribute to small-scale local winds.

Planet-scale differences occur because of solar intensity variations—equatorial regions have greater solar intensity than polar regions.

Differences contribute to global wind patterns, the prevailing winds.

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Atmospheric pressure is greatest near the Earth’s surface because

of the weight of all the air above.

90% of Earth’s atmosphere is in the troposphere.

of warmer temperatures.

of water vapor.

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Driving Forces of Air Motion CHECK YOUR NEIGHBOR

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A) of the weight of all the air above.

Atmospheric pressure is greatest near the Earth’s surface because

of the weight of all the air above.

90% of Earth’s atmosphere is in the troposphere.

of warmer temperatures.

of water vapor.

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Driving Forces of Air Motion CHECK YOUR ANSWER

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A) of the weight of all the air above.

What drives air from areas of high pressure to areas of low pressure?

Convection currents.

Wind.

The pressure-gradient force.

Water vapor.

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Driving Forces of Air Motion CHECK YOUR NEIGHBOR

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C. The pressure-gradient force.

What drives air from areas of high pressure to areas of low pressure?

Convection currents.

Wind.

The pressure-gradient force.

Water vapor.

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Driving Forces of Air Motion CHECK YOUR ANSWER

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C. The pressure-gradient force.

Driving Forces of Air Motion: Temperature-Pressure Relationship

Warm air characteristics:

Warm air expands

Warm air has lower density and lower pressure

Cool air characteristics:

Cool air contracts

Cool air has higher density and higher pressure

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Driving Forces of Air Motion: Temperature-Pressure Relationship

Local winds:

Not all surfaces are heated equally.

Example: Land heats and cools more rapidly than water.

Unequal heating results in pressure differences. And pressure differences result in wind.

Remember: Wind is air that flows horizontally from higher pressure to lower pressure.

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More energy is required to raise the temperature of water than that of land. Once heated, water will retain the heat longer than land. This concept is related to

expansion of warm air.

pressure differences of land and water.

Water’s high specific heat capacity.

expansion of seawater.

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Driving Forces of Air Motion CHECK YOUR NEIGHBOR

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C. Water’s high specific heat capacity.

Driving Forces of Air Motion CHECK YOUR ANSWER

More energy is required to raise the temperature of water than that of land. Once heated, water will retain the heat longer than land. This concept is related to

expansion of warm air.

pressure differences of land and water.

Water’s high specific heat capacity.

expansion of seawater.

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C. Water’s high specific heat capacity.

At a hypothetical school yard there is a blacktop area and a grassy area. On a particularly warm day, a small breeze develops. Air moves from

the grassy area to the blacktop.

the blacktop to the grassy area.

low pressure to high pressure.

Not enough information.

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Driving Forces of Air Motion CHECK YOUR NEIGHBOR

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A. the grassy area to the blacktop.

Driving Forces of Air Motion CHECK YOUR ANSWER

At a hypothetical school yard there is a blacktop area and a grassy area. On a particularly warm day, a small breeze develops. Air moves from

the grassy area to the blacktop.

the blacktop to the grassy area.

low pressure to high pressure.

Not enough information.

Explanation:

Air above the blacktop is hotter (low pressure) than air above the grassy area (higher pressure). Air moves from high to low, so breeze will blow from grassy area to blacktop.

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A. the grassy area to the blacktop.

Driving Forces of Air Motion

Earth’s rotation greatly affects the path of moving air.

Coriolis force: Moving bodies (such as air) deflect to the right in the Northern Hemisphere, to the left in the Southern Hemisphere.

Deflection of wind varies according to speed and latitude.

Faster wind, greater deflection

Deflection greatest at poles, decreases to zero at equator

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Driving Forces of Air Motion

Factors that affect wind:

The pressure gradient force: air moves from high pressure to low pressure

The Coriolis force: apparent deflection of winds due to Earth’s rotation

Frictional force: air moving close to ground encounters friction

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Driving Forces of Air Motion

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Global Circulation Patterns

Global circulation of the atmosphere results from unequal heating of Earth’s surface and Earth’s rotation.

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Global Circulation Patterns

At the equator:

Rising warm, moist air creates a zone of low surface pressure: Doldrums

Trade winds (0º–30º)

At 30º N and S latitude:

Air cools and sinks to create dry air and high pressure: Horse latitudes

Deserts

Westerlies (30º–60º)

At 60º N and S latitude:

Cool, dry air meets warm, moist air to create a zone of low pressure: Polar Front

Polar easterlies (60º–90º)

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The prevailing westerly winds are affected by the Coriolis effect by the deflection of winds

to the right in the Northern Hemisphere and left in the Southern Hemisphere.

to the left in the Northern Hemisphere and right in the Southern Hemisphere.

laterally toward the poles.

westward.

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Global Circulation Patterns CHECK YOUR NEIGHBOR

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A. to the right in the Northern Hemisphere and left in the Southern Hemisphere.

Global Circulation Patterns CHECK YOUR ANSWER

The prevailing westerly winds are affected by the Coriolis effect by the deflection of winds

to the right in the Northern Hemisphere and left in the Southern Hemisphere.

to the left in the Northern Hemisphere and right in the Southern Hemisphere.

laterally toward the poles.

westward.

Explanation:

Winds are named for the direction from which they blow. Westerlies blow from the west to the east.

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A. to the right in the Northern Hemisphere and left in the Southern Hemisphere.

The prevailing winds in North America are westerly—they blow from west to east. Westerly winds contribute to cooling the western coast

in the winter and warming it in the summer.

in the summer and warming it in the winter.

so that the temperature is the same all year long.

and making temperature variations more extreme.

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Global Circulation Patterns CHECK YOUR NEIGHBOR

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B. in the summer and warming it in the winter.

Global Circulation Patterns CHECK YOUR ANSWER

The prevailing winds in North America are westerly—they blow from west to east. Westerly winds contribute to cooling the western coast

in the winter and warming it in the summer.

in the summer and warming it in the winter.

so that the temperature is the same all year long.

and making temperature variations more extreme.

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B. in the summer and warming it in the winter.

Global Circulation Patterns: Oceanic Circulation

Ocean currents are streams of water that move, relative to the larger ocean.

Like the atmosphere, oceans have several vertical layers: surface zone, transition zone, and deep zone.

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Global Circulation Patterns: Surface Currents

Surface currents are created by wind.

Surface ocean currents correspond to the direction of the prevailing winds.

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Global Circulation Patterns: Surface Currents

Ekman transport: Coriolis force causes water currents to deflect up to 45º.

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Global Circulation Patterns: Surface Currents

Factors that influence ocean currents:

For short distances, wind is strongest factor

For longer distances, Coriolis force comes into play:

Coriolis causes surface currents to turn and twist into semicircular whirls called gyres.

Northern Hemisphere gyres rotate clockwise.

Southern Hemisphere gyres rotate counterclockwise.

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Global Circulation Patterns: Surface Currents

Gyres cause heat transport from equatorial regions to higher latitudes.

The Gulf Stream current carries vast quantities of warm tropical water to higher latitudes.

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Global Circulation Patterns: The El Niño Condition

Years in which the Trade winds fail to strengthen are called El Niño years.

El Niño Southern Oscillation influences climate on both sides of the Pacific Ocean.

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Global Circulation Patterns: Deep Water Currents

Deeper waters are driven not by winds but by gravity.

Polar water freezes, increasing the salinity of the liquid water. Cold, salty water continuously sinks to the ocean bottom.

The sinking water pushes deeper water out of the way, causing the bottom water to flow outward along the ocean floor.

A combination of deep-water mixing by ocean-floor tidal stirring and upwelling due to favorable winds brings the deep waters slowly back to the surface.

This conveyor-belt process may take thousands of years.

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EXPERIMENT 13: Radioactive Decay

December 11, 2022/in Uncategorized /by SK

Hands-On Labs SM-1 Lab Manual

EXPERIMENT 13: Radioactive Decay Read the entire experiment and organize time, materials, and work space before beginning.

Remember to review the safety sections and wear goggles when appropriate.

Objectives: To simulate the decay of a hypothetical radioactive element; To graph the results of the simulated decay; and To determine the half-life and decay constant of the element. Materials: Student Provides: Coffee cup Paper, pen, tape Computer with spreadsheet software From LabPaq: Split peas Discussion and Review: Certain elements are made up of atoms whose nuclei are naturally unstable. These elements are said to be radioactive. The nucleus within an atom of a radioactive element will decay into the stable atomic nucleus of another element by emitting or capturing atomic particles. The unstable element is called the “parent” element and the stable element is called the “daughter” element. The continuous process of disintegration of unstable radioactive nuclei is called radioactive decay. It is impossible to predict which particular nuclei and when any one of the nuclei in a sample will disintegrate. However, it is possible to predict the average rate of nuclei that will decay during a given time period. This percentage, expressed as a decimal, is called the decay constant, . Mathematically, the decay process is modeled exponentially:

where No is the original number of nuclei present and N is the number of nuclei present at time t. The half-life, t1/2 of a radioactive sample is the time required for one half of the nuclei present to decay. If the above exponential equation is solved for t when N = No /2, the result is (Remember “ln” refers to the natural log):

We will assume that once an unstable “parent” decays the resulting “daughter” is stable and can emit no more particles. In more complicated cases the daughter might be unstable as well but we will not deal with that situation now.

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PROCEDURES: In this exercise, you will calculate the decay constant and half-life of a sample using split peas to simulate the decay of radioactive nuclei. Peas lying on their flat side will be “parents” representing nuclei not yet decayed. Peas lying on their rounded side will be “daughters” representing the decayed nuclei. Each trial represents one unit of time. We assume a time interval of 2 minutes for each trial, but since this is a simulation, we could have assumed any time interval we wanted. 1. Set up a data table as follows to record your observations. Data Table: Trials Time –

minutes Parents = Peas lying flat

# per trial Daughters = Peas on rounded side

# per trial cumulative # 0 0 50 0 0 1 2 2 4 3 6 4 8 Etc. 0 50

2. Tape several sheets of white paper to your work table. Having this white background

will make counting the peas easier. 3. Count out exactly 50 individual split peas and put them into a coffee cup. Record 50

peas under time trial 0 on the data table. 4. Cover the cup with your hand, shake the contents for several seconds, and pour the

peas from the cup onto the paper in such a way that a single layer of peas is formed. 5. Count the number of parent peas lying on their flat side, and the number of daughter

peas lying on the rounded side. Record these values under Trial 1 of the Data Table. 6. Set the daughters aside, but put the parent peas from the trial back into the cup.

Shake as before and pour them back onto the paper for another trial. 7. Again, count and record both the flat lying parent peas and the rounded-edge lying

daughter peas. For the parents, record only the number of peas counted. For the daughters, you should record the number counted, then add that number to the previous count so that a running cumulative total of daughters can also be recorded. See the example on the following page for clarification.

8. Repeat this process until no split peas are remaining.

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Example: The example below assumes that for trial 1 you had 23 flat lying parents and 27 daughter peas lying on the rounded sides. Next, you used only the 23 parents for trial 2 and got 12 parents and 11 daughters. Under trial 2, you record the 12 parents and 11 daughters, then add the 11 daughters to the previous count of 27 for a cumulative total of 38 daughters. Example DATA TABLE: Trials Time –

minutes Parents = Peas lying flat

# per trial Daughters = Peas on rounded side

# per trial cumulative # 0 0 50 0 0 1 2 23 27 27 2 4 12 11 38 3 6 4 8

Graphing: 1. Graph the results of your experiment. Plot the number of parent atoms (peas)

remaining after each trial on the y-axis. Plot the time on the x-axis. 2. Construct another graph. Plot the number of daughter atoms (peas) after each

observation on the y-axis. Plot the time of the observation on the x-axis. 3. Explain the difference in the two graphs. 4. Determine the half-life of this hypothetical element from your graph.

5. Using the equation calculate the decay constant: (ln 2 = 0.693) λ = 0.693/ t ½ Remember “ln” refers to the natural log.

SM-1 Manual COLOR 105 08-17-07.pdf

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EXPERIMENT 13: Radioactive Decay

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