ALEX Learning Activity


Cat-Traption and the Conservation of Energy

A Learning Activity is a strategy a teacher chooses to actively engage students in learning a concept or skill using a digital tool/resource.

You may save this Learning Activity to your hard drive as an .html file by selecting “File”,then “Save As” from your browser’s pull down menu. The file name extension must be .html.
  This learning activity provided by:  
Author: Lisa Rhinehart
System:Pell City
School:Pell City Board Of Education
  General Activity Information  
Activity ID: 2010
Cat-Traption and the Conservation of Energy
Digital Tool/Resource:
Animation for the Conservation of Energy
Web Address – URL:

This learning activity shows how energy is transferred from one object to another and can engage students in a discussion related to kinetic energy. The students will observe an animation and record the movement of the objects much like that of a "Rube Goldberg" contraption that sets a chain of events in motion to complete a task. The students will then answer a series of questions related to the animation and apply concepts associated with the law of conservation of energy. 

This activity was created as a result of the GAP Project Resource Summit.

  Associated Standards and Objectives  
Content Standard(s):
SC2015 (2015)
Grade: 8
Physical Science
16 ) Apply the law of conservation of energy to develop arguments supporting the claim that when the kinetic energy of an object changes, energy is transferred to or from the object (e.g., bowling ball hitting pins, brakes being applied to a car).

NAEP Framework
NAEP Statement::
P12.16: Total energy is conserved in a closed system.

NAEP Statement::
P8.12a: When energy is transferred from one system to another, the quantity of energy before transfer equals the quantity of energy after transfer.

NAEP Statement::
P8.12b: For example, as an object falls, its potential energy decreases as its speed, and consequently, its kinetic energy increases.

NAEP Statement::
P8.12c: While an object is falling, some of the object's kinetic energy is transferred to the medium through which it falls, setting the medium into motion and heating it.

NAEP Statement::
P8.8a: Objects and substances in motion have kinetic energy.

NAEP Statement::
P8.8b: For example, a moving baseball can break a window; water flowing down a stream moves pebbles and floating objects along with it.

Unpacked Content
Scientific And Engineering Practices:
Engaging in Argument from Evidence
Crosscutting Concepts: Energy and Matter
Disciplinary Core Idea: Energy
Evidence Of Student Attainment:
  • Apply the law of conservation of energy to develop arguments supporting the claim that when the kinetic energy of an object changes, energy is transferred to or from the object.
Teacher Vocabulary:
  • Law of Conservation of Energy
  • Argument
  • Claim
  • Kinetic Energy
  • Energy Transfer
  • System
Students know:
  • Kinetic energy is energy that an object possesses due to its motion or movement.
  • Changes in kinetic energy may include changes in motion, temperature, or other observable features of an object.
  • When the kinetic energy of an object changes, energy is transferred to or from that object.
  • When the kinetic energy of an object increases or decreases, the energy of other objects or the surroundings within the system increases or decreases, indicating that energy was transferred to or form the object.
  • The Law of Conservation of Energy states that in a closed system, the total energy of the system is conserved and energy is neither created nor destroyed.
Students are able to:
  • Make a claim about a given explanation or model for a phenomenon, including the idea that when the kinetic energy of an object changes, energy is transferred to or from that object .
  • Identify and describe the given evidence that supports the claim.
  • Evaluate the evidence and identify its strengths and weaknesses.
  • Use reasoning to connect the necessary and sufficient evidence and construct the argument.
  • Present oral or written arguments to support or refute the given explanation or model for the phenomenon.
Students understand that:
  • The law of conservation of energy states that in a closed system, the total amount of energy remains constant and energy is neither created nor destroyed.
  • Energy can be converted from one form to another, but the total energy within the system remains fixed.
  • Energy can be transferred between objects in the system.
AMSTI Resources:
AMSTI Module:
Electricity, Waves, and Information Transfer

Alabama Alternate Achievement Standards
AAS Standard:
SCI.AAS.8.16- Make observations about energy transfers in common everyday occurrences (e.g., bowling ball hitting pins, brakes being applied to a bicycle or car).

Learning Objectives:

  1. The student will understand that energy is not created or destroyed but transferred from one object to or from another object.
  2. The student will identify changes in kinetic energy.
  3. The student will observe the energy transformations of an object. 
  Strategies, Preparations and Variations  

1. The teacher will show the animation to the whole class.

Complete Run Through (Flash Required)

2. As the students watch the animation, they will observe the movements of the Cat-Traption and create a list of the movements on a teacher created document with the diagram from the animation (see the Advanced Preparation Section for the diagram). The student will name the item and what caused it to move (see list below). Students' answers may not be identical to those used below and the animation may need to be played more than once.

  1. Tug on tether caused by cat moves stick on a pivot
  2. Stick knocks the tethered ball off a pedestal
  3. Ball drops and swings
  4. Ball knocks steel ball #1
  5. Steel Ball #1 knocked into steel ball #2
  6. Electric switch turns on the electromagnet
  7. Movement of metal plate releases cup
  8. Cup rises on spring
  9. Rising of cup releases toy mouse
  10. Solar cell operates an electric motor
  11. Electric motor turns a wheel with projecting rod
  12. Rod turns the wheel a bit more with each turn
  13. Axel reels in the string


  1. String pulls sponge from beneath end of a sealed bag
  2. As the end of the bag drops, water flows onto Alka-Seltzer tablets
  3. Tablets fizz, inflating the bag
  4. Inflation of the bag tips over the box of cat food
  5. Tipping of the box causes the cat food to spill
  6. Cat eats food from the bowl

3. Within their groups, or in pairs, the students will compare answers and make adjustments as needed.

4. Next, return to the animation, and as a whole group, move through the animation again. Read the questions aloud as the students write their responses on the same sheet of paper (found in the Cat-Traption Activity section). After they make their selection from the multiple choice questions A-E, have them to explain their answer. Before moving on to the next question, poll the class to gauge their understanding and then show the correct answer and explanation. Instruct the students to make corrections as needed. Continue in this manner until all questions have been assessed.

Correct Answers for A-E

A. What is the ultimate source of the energy that starts the Cat­‐Traption operation?

 The Sun- The cat's food source came from grain which received its energy from the sun.

B. Not all the energy of the first ball causes the second ball to roll. What happened to the rest of the energy?

Both of the above- (A. It is converted to heat and B. It is converted to sound)-Energy is never used completely up, some is converted to heat, and some is converted to sound.

C. What energy causes the cup to rise, releasing the mechanical mouse?

Elastic potential energy from the spring-The spring has potential energy when it is compressed and when it is stretched it has kinetic energy causing the cup to rise.

D. What conditions would reduce the amount of energy transferred from the solar cell to the motor?

All of the above (Raising the lamp higher above the solar cell, Moving the solar cell partially out from under the lamp, or Using a dimmer bulb in the lamp)

E. Did the cat feed itself?

No, because people set up the Cat-Traption that fed the cat.

Answers may vary.

 5. Once the students have completed the questions, they will use the diagram and label five energy transformations.

6. Finally, the teacher will give each student a note card. On the front of the note card the student will:

  • Define the Conservation of Energy
  • Define Kinetic Energy 
  • Provide an example of an energy transformation.
  • On the back of the note card, the student will illustrate the example and label the transfer of kinetic energy. (roller coaster, bowling, pool, etc.)
Assessment Strategies:

The students will be assessed based on teacher observations as the students work through the questions and label the diagram.

Students will be assessed on completion of the note card.

Advanced Preparation:

Make sure the computer has Flash.

Larger Version of the animation can be shown by using Firefox.

Chrome shows a very small animation but you can increase the screen by holding the control key and the plus sign at the same time.

Copy the image of the Cat-Traption on a sheet of paper for students to label and work through questions.



 Image result for cat traption image

Variation Tips (optional):
Notes or Recommendations (optional):

If this activity is part of a pre-assessment then students may have difficulty with some of the vocabulary in the activity.

  Keywords and Search Tags  
Keywords and Search Tags: