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Simple Machines

published on: 9/10/2008

Contributing Teacher(s): Donetta Horky,

Subject Area: Science/Physical,

Grade Range: Middle Grades (6-8)

Materials Needed:

• Multiple Pulleys String or fishing line
• Various Masses (slotted and regular)
• Ringstand
• Clamps
• Mass Hanger
• Meterstick
• Calculator
• Wheel & Axle
• Ramp
• Cart
• Single Pulley
• Laboratory Jack (or books)

Objective: Student Objectives:

1. The student will be able to define what a simple machine is and its purpose
2. The student will be able to recognize the meaning of mechanical advantage and efficiency
3. The student will be able to communicate what a formula means in their own words

Essential Question:

Instructional Strategy: Cooperative Learning

Process Standards: Goal 1.1 develop questions and ideas to initiate and refine research
Goal 1.2 conduct research to answer questions and evaluate information and ideas
Goal 1.4 use technological tools and other resources to locate, select and organize information
Goal 1.6 discover and evaluate patterns and relationships in information, ideas and structures
Goal 1.8 organize data, information and ideas into useful forms (including charts, graphs, outlines)
Goal 1.10 apply acquired information, ideas and skills to different contexts as students, workers, citizen

Content Standards: SC2, SC8,

G.L.E.:

Time Allowance: Elicitation: 2/45 minute class periods, Activity 1- Pulley Lab: 2-3 - 45 , – Wheel and Axle Lab: 2- 45 min, Activity 3 – Inclined Plane: 2- 45 minute class periods

Technological Resources:

Extensions:
We use machines in our lives every day. Answer the following questions on your own. You will then work in small groups and put together a white board for the whole class to discuss.

1. What does the term machine mean to you? Please include 3 or more characteristics of a machine.
2. Do you think machines need energy? Why or why not?
3. List 5 examples of a simple machine and how you use it in your every day life.

Integration:

Differentiation:
Activity Modifications: To begin each activity, the instructor should provide an overview of the objectives and instructions for completing the activity for the day. Learning disabled students should be paired with students that have a higher level of learning and understanding of the concept. This form of peer tutoring will provide an opportunity for the students to communicate their thoughts in a less threatening environment. More advanced students should be able to complete the activities with little instruction from the instructor. Using their partner(s), the students should be able to assist one another in completing the required activities, correctly, in the given amount of time.

Assessment:
Please see lesson

Description: Overview: Students will build upon their skills in explaining and understanding how simple machines work. Incorporated into these skills will be activities investigating pulleys, inclined planes, and wheel and axle. These activities will explore the following concepts: • Understand how each of these simple machines work. • Understand the mechanical advantage and efficiency of a machine.

Comments:

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Classroom Component:

Assessment: Pre-Test/Post-Test Simple Machines
Name: ____________________ Date: _______________ Hr: ________

All answers must be in complete sentences (Power Answers)

1. What is the purpose of a machine?
2. On the diagram, label the load and the effort.
3. Do you view a transfer of energy in a pulley system? Draw an energy diagram showing a pulley system. Be sure to label the energy source, energy receiver, and type of interaction.
4. Compare and contrast Actual Mechanical Advantage and Ideal Mechanical Advantage. Explain your answer.
5. What effect does increasing the height of a ramp have on the machine’s efficiency? Explain your answer.
6. If you were building a handicapped accessible building, what measurements would need to be considered in order to build a ramp requiring the least amount of force by an individual using a wheelchair?
   a. A ramp with a height of 3m and 10m long
   b. A ramp with a height of 2m and 10m long
   c. A ramp with a height of 1m and 10m long
7. Can a machine ever be 100%, or greater, efficient? Explain your answer.
8. Would the value you determined for efficiency indicate that the useable energy coming out of the machine is the same as the energy coming in? If not, how do these energies compare?

Activity Modifications: To begin each activity, the instructor should provide an overview of the objectives and instructions for completing the activity for the day. Learning disabled students should be paired with students that have a higher level of learning and understanding of the concept. This form of peer tutoring will provide an opportunity for the students to communicate their thoughts in a less threatening environment.
More advanced students should be able to complete the activities with little instruction from the instructor. Using their partner(s), the students should be able to assist one another in completing the required activities, correctly, in the given amount of time.
Pre/Post Test Assessment Modifications: Modifications for this pre/post test assessment could entail making some, or all, of the questions multiple choice for the learning disabled student(s). Another modification could be accepting short answers that are not in complete sentences, or giving a verbal test to students with low levels of reading.

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Pre/Post Test Rubric

1. What is the purpose of a machine?

3pts. – 1—complete sentence, 1—changing size, 1—changing direction
Changing the size or direction of the force. Does NOT make work easier.

2. On the diagram, label the load and the effort.

2pts. – 1—man is effort; 1—weight is load

3. Do you view a transfer of energy in a pulley system? Draw an energy diagram showing a pulley system. Be sure to label the energy source, energy receiver, and type of interaction.

7 pts. 1—yes, 1—type of interaction (Mechanical Interaction), 1—Energy Source (Input Force), 1—change in energy (decrease GPE), 1—Energy Transfer (Mechanical Energy), 1—Energy Receiver (Load), 1—change in energy of load (increase GPE)

4. Compare and contrast Actual Mechanical Advantage and Ideal Mechanical Advantage. Explain your answer.

4pts. 1— Actual Mechanical Advantage: ratio of the output force and input force
1—Ideal Mechanical Advantage: ratio of the input distance and output distance
1—No friction when measuring distances therefore IMA will always be greater the AMA
1—Explanation in complete sentences

5. What effect does increasing the height of a ramp have on the machine’s efficiency? Explain your answer.

2Pts. 1—The height and the machines efficiency are inversely proportional. When one increases, the other decreases due to gravity creating more friction.
1—Explanation in complete sentences.

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6. If you were building a handicapped accessible building, what measurements would need to be considered in order to build a ramp requiring the least amount of force by an individual using a wheelchair?
a. A ramp with a height of 3m and 10m long
b. A ramp with a height of 2m and 10m long
c. A ramp with a height of 1m and 10m long

2pts. – C

7. Can a machine ever be 100%, or greater, efficient? Explain your answer.

3pts. 1—No, 1—Friction, 1—Explanation is in complete sentences.

8. Would the value you determined for efficiency indicate that the useable energy coming out of the machine is the same as the energy coming in? If not, how do these energies compare?

3pts. 1—No, 1—Some energy is changed not lost due to friction, 1—Explanation is in complete sentences.

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Simple Machines

Major Concept(s): Simple Machines (Pulleys, Wheel and Axle, Inclined Plane)

Missouri Knowledge Standards: Science
In Science, students in Missouri public schools will acquire a solid foundation which includes knowledge of

2. properties and principles of force and motion
7. processes of scientific inquiry (such as formulating and testing hypotheses)

GLE’s:

• SC7.1.A.c. Conduct a valid experiment.
• SC7.1.B.c. Use a variety of tools and equipment to gather data
• SC1.2.F.c. Explain energy is not lost but conserved as it is transferred and transformed.
• SC2.2. Forces affect motion
• SC2.2.A. Forces are classified as either contact forces (pushes, pulls, friction, buoyancy) or non-contact forces (gravity, magnetism), that can be described in terms of direction and magnitude
• SC2.2.F Simple machines (levers, inclined planes, wheels and axles, pulleys) affect the forces applied to an object and/or direction of movement as work is done
• SC2.2.F.a. Recognize examples of work being done on an object (force applied and distance moved in the direction of the applied force) with and without the use of simple machines
  b. Calculate the amount of work done when a force is applied to an object over a distance
  (W = F x d)
  c. Explain how simple machines affect the amount of effort force, distance through which a force is applied, and/or direction of force while doing work
  d. Recognize the amount of work output is never greater than the amount of work input, with or without the use of a simple machine
  e. Evaluate simple machine designs to determine which design requires the least amount of effort force and explain why
  

Student Objectives:

• TSWBAT define what a simple machine is and its purpose
• TSWBAT recognize the meaning of mechanical advantage and efficiency
• TSWBAT communicate what a formula means in their own words

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Time Required:

• Elicitation: 2- 45 minute class periods (includes discussion)
• Activity 1- Pulley Lab: 2-3 - 45 minute class periods
• Activity 2 – Wheel and Axle Lab: 2- 45 minute class periods
• Activity 3 – Inclined Plane:  2- 45 minute class periods

Background information regarding simple machines:

There are six basic simple machines: pulley, wheel and axle, inclined plane, wedge,  lever, and screw.  The students  should have a basic understanding of what a simple machine is and why they are used.

Activities:

• Elicitation: Why do we use machines in our daily lives?
• Activity 1: Pulley Systems
• Activity 2: Wheel and Axle
  
• Activity 3: Inclined Plane

Elicitation: Essential Questions

We use machines in our lives every day.  Answer the following questions on your own.  You will then work in small groups and put together a white board for the whole class to discuss. 

•  What does the term machine mean to you?  Please include 3 or more characteristics of a machine. 
• Do you think machines need energy? Why or why not?
•  List 5 examples of a simple machine and how you use it in your every day life.

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Now set up one fixed pulley with a load of 500 g and an input force of 500 g.  The load should begin on the counter.  Students will need to measure from the counter to the bottom of the input force.

Input/Output of a One Pulley system

	Weight lifted (load)     (Newtons)	Input force (effort)     (Newtons)	Height load is lifted (output distance)   (meters)	Input distance (distance over which effort force acts) (meters)	Ratio of Load/Effort     (no unit)	Ratio of distance input/height input   (no unit)	Load/Effort divided by distance input/height output (%)
1 Pulley
SHOW WORK

Following the lab, engage in a class discussion of simple machines.

 

 

 

 

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Pulley System:
Problem: What effect does increasing the number of pulleys on the mechanical advantage of a simple machine?
Hypothesis:  __________________________________________________________________
______________________________________________________________________________
Materials:
Multiple Pulleys                        String or fishing line                   Various Masses (slotted and regular)
Ringstand                                 Clamps                                     Mass Hanger
Meterstick                                Calculator
Procedure:

1.  Set up the pulley system your group has been assigned. Write down the number of the system ________.   Look carefully at the manner in which the strings are wound around the pulleys (you will need around 12 feet of fishing line or string.)

2.  Attach a 1 Kg mass as your pulley system load (output force).  One person in your group will have to pull the string taunt to prevent the system from falling apart.
3. Carefully attach the mass hanger where the input (effort) force is pictured.  Predict the least amount of mass you will need to lift the load (output force).    Place your prediction here: ________
4. Attach enough mass so when you lightly tap the input (effort) force the load (output force) will rise at a slow constant speed.  Record the amount of mass here: ______________________ (***Measure in Kg***)

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5. Measure the distance from the counter to the bottom of the mass (output distance) representing the load (output force).   Record your data here: ___________________  ( ***BE SURE TO MEASURE IN METERS***)
6. Measure the distance from the counter to the bottom of the mass representing the input (effort) force (at its highest point). Record your data here: _____________________ (input distance)
7. After all measurements are complete, get a data table from your instructor.  Fill out the information you have just recorded on the table.  Remaining pulley system data will be placed directly on table.
8. Carefully remove your masses from the mass hanger after you have gently lowered your load (output force).  Proceed to the next available station.

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Analysis Questions: 

1.  The Force in (Effort) is marked on the diagram.  Explain why this represents the input (effort) force.  In which direction does this force act (up or down)?

 

 

2. What distance will represent the input distance over which the input force acts?  Please explain your answer.

 

 

 

3. The Load (Force Output) is indicated in the diagram.  What will represent the output distance over which the output force acts?

 

 

4. How do the two values, load (output force) and the input force (effort) compare?  Are they equal to each other or is one bigger/smaller than the other?

 

 

5.  If you said yes in question 4, explain the cause of the difference.

 

 

6.  How do these two values, the output distance and the input distance compare?  Are they equal to each other or is one bigger/smaller than the other? 

 

 

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7. If you said yes in question 6, explain the cause of the difference.

 

 

8. Calculate the ratio of output force to input force, be sure to show your work.  Record your answer here and in the data table.  This ratio (output force/input force) represents the Actual Mechanical Advantage of the machine.   Mechanical Advantage does not have any units.

 

 

 

9. In your own words, what does the Actual Mechanical Advantage of a machine represent? (Use your data as evidence for your representation).

 

10. Calculate the ratio of input distance to output distance, be sure to show your work.  Record and enter here and in the data table.  This ratio (input distance/ output distance) represents the Ideal Mechanical Advantage of the machine.

 

 

11. In your own words, what does the Ideal Mechanical Advantage of a machine represent? (Use your data as evidence for your representation).

 

 

12. How do the two ratios predicted and calculated above compare?  Are the ratios equal to each other or is one bigger/smaller than the other?

 

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13.  If there is a difference in question 12, explain why you think that difference occurs?

 

 

14. Lastly, calculate the ratio of Load (output force)/Effort (input force) divided by the ratio of distance input/distance output.  Record that value here and in the last column of the table above.  This value represents the efficiency of the machine.

 

Is the value

 

Can you think of a way that the value would = 1?

 

Can you think of a way that the value would be > 1?

 

15.  Take your answer from question 14, and multiply it by 100, this gives you a percent. (Efficiency is measured as a percent.)

 

 

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On the table below, please record all the values you measured or calculated above for your pulley system per the column headings. 

Input and Output Measurements of Pulley Systems

Pulley System No.	Output Force (Load)	Input Force (Effort)	Distance load is lifted-(output distance)	Distance over which effort force acts (input distance)	Ratio of Load/Effort   (AMA)	Ratio of input distance / output distance (IMA)	Efficiency % AMA/IMA
2
3
4
5
6
7

 Summarizing Questions:

1. What relationship do you see between the weight lifted (load) and the input force (effort) as you change the pulley system from No. 2 – No. 7?
   
   
   
   
2. What relationship do you see between the input distance and the height output as you change the pulley system from No. 2 – No. 7?
   
   
   
   
   
3. What does this tell you about the purpose or characteristics of a machine?
   

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4. Do you view a transfer of energy in this machine?  Draw an energy diagram.
   
   
   
   

Application:

5. Look carefully at the number of strings wound around each pulley system.  Count the number of strings supporting the Load on each pulley – compare it to the ratio you calculated for the Ideal Mechanical Advantage.  How do they compare?  What is the function of the strings? 

6. Can you think of three examples of pulley systems you have used in your everyday life?

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Wheel & Axle Lab
Name _____________________________   Date ________   Hour __________

Problem:  What effect does increasing the diameter of the wheel have on the efficiency of the machine?

Hypothesis:

Materials:

• Ringstand                    
• String or fishing line                  
• Various Masses (slotted & regular)                  
  
• Wheel & Axle             
• Mass Hanger                           
• Calculator
  
• Clamps            
• Meter stick      

Preliminary Questions:

1. Look at the wheel and axle and note how the diameters of the pulleys compare. What difference do you think the diameters will make?

 

 

 

2. Think about pedaling up a steep hill on your bike.  If you were only given one of your gears to use to help you up the hill, would you choose the largest diameter gear or the smallest diameter gear?  Give your reasoning why.

 

 

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Procedure:     

1. Set up the wheel and axle system using the wheel and axle, clamp, and ringstand as shown in the diagram below.           

 

2. Attach 1 kg mass as the load.  Be sure your string begins on the smallest diameter pulley.
3. Carefully attach the mass hanger where the effort is pictured. 
4. Attach enough mass on the mass hanger so when you lightly tap it, the load will rise at a slow constant speed.  Record: ______ (kg)
5. Measure the distance from the counter to the bottom of the mass that was lifted (h output, otherwise known as output distance).  Record: _______ (m)
6. Measure the distance from the counter to the bottom of the mass representing the effort force (h input, otherwise known as input distance).  Record: _______ (m)
7. Repeat steps 2 – 6 for the other two diameter pulleys.  Record all data on the data table.

Analysis Questions:

1. The Force out (Load) and Force in (Effort) are labeled in the diagram.  Explain why you think these names are appropriate for these forces.  What is the difference between the load and effort?

 

 

 

 

2. Calculate the ratio of the load to the effort for each diameter pulley.  This ratio (output force/input force) respresents the Actual Mechanical Advantage (AMA) of the machine.

 

 

3. In your own words, what do you think the Actual Mechanical Advantage of a machine represents? (Use your data as evidence for your representation).

 

 

4. Calculate the ratio of height input force moves down (h input) to the height the load is lifted (h output) and enter here.  This ratio (height input/height output) represents the Ideal Mechanical Advantage  (IMA) of the machine.

 

5. In your own words, what do you think the Ideal Mechanical Advantage of a machine represents? (Use your data as evidence for your representation).

 

 

6. Lastly, calculate the ratio of Load (output force)/Effort (input force) divided by the ratio of height input/height output.  [AMA/IMA]. Record that value here. This value represents the efficiency of the machine.
   
   

Is the value

Can you think of a way that the value would = 1?

Can you think of a way that the value would be > 1?

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Name__________________________           Group_______________________

Input and Output of a Wheel & Axle

Pulley No.	Weight lifted (Load)	Input Force (Effort)	Height output (height load moves)	Height input (height effort force moves)	Ratio of Load/Effort (AMA)	Ratio of height input/height output (IMA)	Efficiency % Load/Effort divided by height input/height output
No. 1
No. 2
No. 3

 

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Summarizing Questions:

7. What, if any, relationship do you see between the weight lifted (Load) and the input force (effort) as you move the string from the smallest diameter pulley to the largest diameter pulley? 

 

8.  Do you view a transfer of energy in this machine?

 

9. Where is the energy coming from (energy source) and what is receiving the energy (energy receiver)?

 

10. Please describe using an energy diagram.

 

11. Would the value you determined for efficiency indicate that the useable energy coming out of the machine is the same as the energy coming in?  If not, how do these energies compare?

 

12. If the energy coming out of a machine is less than the energy input, what do you think happened to the energy?

 

13.  If the useful energy coming out of a machine is less than the energy you put into the machine, why would you want to use it?  (Refer to the purpose or characteristics of the machine determined earlier).

 

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Application:

14. Think of your own example of a wheel and axle that you find helpful in your daily life.  Explain why it is helpful.

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Inclined Plane Lab
Name _______________________________     Date _________                 Hour _______

Problem:  What effect does the height of an inclined plane have on the amount of work being done?
Hypothesis:

Materials:

• Ramp                                                 
• Cart                            
• Single Pulley
  
• String or fishing line                              
• Laboratory Jack (or books)
  
• Meter stick                                          
• Masking Tape             
• Calculator
  
• Slotted masses
  

Procedure:                 

1.  Set up an Inclined Plane using a laboratory jack (or 1 book) under one end of the track.  Compress the jack fully and attach a pulley to the elevated end of the track. 
2. Find the mass of the cart in kg.  Record: __________________
3. Attach a cart to the string that goes to the single pulley as shown below.
4. Make a loop in the input end of the string and attach the mass hanger.
5. Using masking tape mark .5 m on the track.  The cart should be positioned behind one piece the masking tape.  Distance “L” represents the distance over which the effort (input) force acts.
6. Slowly add masses to the mass hanger until the cart moves at a slow constant speed toward the second piece of masking tape.   (You will need to give the masses a slight downward tap.) Record:  ______________________

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7.  Now measure the height of the track where the second piece of masking tape is located.   (Reminder: you will need to subtract the starting height (first piece of tape) from the second piece of tape).  Record: _________________ m   This distance “h”” represents the vertical height the output distance (Load) is lifted.

 

8. Once you have completed the first trial and calculations, predict what would happen to the value of the input force as you increase the height of the incline.  Please explain your prediction here.

 

 

 

9. Repeat steps 6 and 7 after you increase your ramp height.  If you are using books, add two more book of the same thickness. If you are using the laboratory jack, increase your height by 0.02 m (or 2 cm).

10. Record your data in the data table.

Analysis Questions: 

1.  The Force in (Effort) is marked on the diagram.  Explain why this represents the input (effort) force. 

 

.

2. What do you think will represent the output force (Load)?  Think about the purpose of this inclined plane as a machine.  What are you trying to lift? 

 

 

3. How do these two distance values (input distance and output distance) compare?  Are they equal to each other or is one bigger/smaller than the other? Why? Circle the correct MA:  IMA or AMA

 

4. How do these two values – the Weight Lifted (output force - load) and the input force (Effort) - compare?  Are they equal to each other or is one bigger/smaller than the other? If there is a difference, what do you think is the cause? Circle the correct MA:  IMA or AMA

 

 

 

5. Calculate the ratio of output force to input force below. Record here and in the data table.

 

 

6. Calculate a ratio of the distance the input force acts to the height the load is lifted (height output). Record here and in the data table.  (input distance/height output)

 

 

7. How do the two ratios calculated above compare?  Are they equal to each other or is one bigger/smaller than the other? If there is a difference, why do you think that difference occurs?

 

 

8. Lastly, calculate the ratio of Load (output force)/Effort (input force) divided by the ratio of distance input/height output.  Record that value here.  This value represents the efficiency of the machine.

 

Is the value

 

Can you think of a way that the value would = 1?

 

Can you think of a way that the value would be > 1?

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Name ___________________________             Group __________________________

Input and Output Force of an Inclined Plane

Run No.	Weight lifted (Load)	Input Force (Effort)	Height - vertical height  load is lifted (output distance “h”)	Distance input (distance over which effort force acts (L)	Ratio of Load/Effort	Ratio of distance input/height output	Efficiency % Load/Effort divided by distance input/height output
Trial #1
Trial #2

Summarizing Questions:

9. What, if any, relationship do you see between the weight lifted (Load) and the input force (effort) as you change the height from Trial #1 to Trial #2?

 

 

10.  Do you view a transfer of energy in this machine?  Please describe using an energy diagram.

 

 

11. If the energy coming out of a machine is less than the energy input, what do you think happened to the energy?

 

 

Application:

12. List two examples of inclined planes that you use in your daily life.  Identify the effort and load.

 

 

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Assessment: Pre-Test/Post-Test                            Simple Machines
Name: ____________________               Date: _______________                     Hr: ________

All answers must be in complete sentences (Power Answers)

1. What is the purpose of a machine?

 

2. On the diagram, label the load and the effort.

   

3. Do you view a transfer of energy in a pulley system? Draw an energy diagram showing a pulley system. Be sure to label the energy source, energy receiver, and type of interaction.

 

 

 

4. Compare and contrast Actual Mechanical Advantage and Ideal Mechanical Advantage.  Explain your answer.

 

 

 

5. What effect does increasing the height of a ramp have on the machine’s efficiency? Explain your answer.

 

 

6. If you were building a handicapped accessible building, what measurements would need to be considered in order to build a ramp requiring the least amount of force by an individual using a wheelchair?
1. A ramp with a height of 3m and 10m long
2. A ramp with a height of 2m and 10m long
3. A ramp with a height of 1m and 10m long

7. Can a machine ever be 100%, or greater, efficient?  Explain your answer.

 

 

8. Would the value you determined for efficiency indicate that the useable energy coming out of the machine is the same as the energy coming in?  If not, how do these energies compare?

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Pre/Post Test Rubric

1. What is the purpose of a machine?

3pts. – 1—complete sentence, 1—changing size, 1—changing direction
Changing the size or direction of the force.  Does NOT make work easier.

2. On the diagram, label the load and the effort.

   

   
2pts. – 1—man is effort; 1—weight is load

3. Do you view a transfer of energy in a pulley system? Draw an energy diagram showing a pulley system. Be sure to label the energy source, energy receiver, and type of interaction.

7 pts. 1—yes, 1—type of interaction (Mechanical Interaction), 1—Energy Source (Input Force), 1—change in energy (decrease GPE), 1—Energy Transfer (Mechanical Energy), 1—Energy Receiver (Load), 1—change in energy of load (increase GPE)

4. Compare and contrast Actual Mechanical Advantage and Ideal Mechanical Advantage.  Explain your answer.

4pts. 1— Actual Mechanical Advantage: ratio of the output force and input force
1—Ideal Mechanical Advantage: ratio of the input distance and output distance
1—No friction when measuring distances therefore IMA will always be greater the AMA
1—Explanation in complete sentences

5. What effect does increasing the height of a ramp have on the machine’s efficiency? Explain your answer.

2Pts. 1—The height and the machines efficiency are inversely proportional.  When one increases, the other decreases due to gravity creating more friction.
1—Explanation in complete sentences.

6. If you were building a handicapped accessible building, what measurements would need to be considered in order to build a ramp requiring the least amount of force by an individual using a wheelchair?
1. A ramp with a height of 3m and 10m long
2. A ramp with a height of 2m and 10m long
3. A ramp with a height of 1m and 10m long

2pts. – C

7. Can a machine ever be 100%, or greater, efficient?  Explain your answer.

3pts. 1—No, 1—Friction, 1—Explanation is in complete sentences.

8. Would the value you determined for efficiency indicate that the useable energy coming out of the machine is the same as the energy coming in?  If not, how do these energies compare?

3pts. 1—No, 1—Some energy is changed not lost due to friction, 1—Explanation is in complete sentences.

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Activity Modifications:  To begin each activity, the instructor should provide an overview of the objectives and instructions for completing the activity for the day.  Learning disabled students should be paired with students that have a higher level of learning and understanding of the concept.  This form of peer tutoring will provide an opportunity for the students to communicate their thoughts in a less threatening environment. 
More advanced students should be able to complete the activities with little instruction from the instructor.  Using their partner(s), the students should be able to assist one another in completing the required activities, correctly, in the given amount of time.

Pre/Post Test Assessment Modifications:  Modifications for this pre/post test assessment could entail making some, or all, of the questions multiple choice for the learning disabled student(s).  Another modification could be accepting short answers that are not in complete sentences, or giving a verbal test to students with low levels of reading.

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