MS-PS3-1: Kinetic Energy Relationships

MS-PS3-1
Kinetic Energy Relationships

Middle School

​

Learning Objectives

• Define potential and kinetic energy and describe how they are converted and transferred.

• Explain how mass and height affect an object's potential energy.

• Construct and interpret graphical displays of data for kinetic energy.

• Describe the relationship between kinetic energy, mass, and speed.

Key Vocabulary

​

Potential Energy

Potential energy is the stored energy an object has due to its position or height.

​

Kinetic Energy

Kinetic energy is the form of energy that an object possesses while it is in motion.

​

Energy Transfer

This is the process by which energy moves from one system or object to another one.

​

Mass

Mass is the measure of the total amount of matter that is contained within an object.

​

Friction

Friction is a force that opposes motion between surfaces, often creating thermal or heat energy.

​

Linear Relationship

A linear relationship describes a direct correlation between two variables and forms a straight line when graphed.

Key Vocabulary

​

Non-linear Relationship

A relationship that does not form a straight line when it is graphed.

What are Potential and Kinetic Energy?

• Potential energy is stored energy based on an object’s position.

• Kinetic energy is the energy of motion, like a rolling marble.

• Stored potential energy converts into kinetic energy as the marble rolls down.

Multiple Choice

Which of the following best describes potential energy?

• Energy that is stored based on an object’s position.

• Energy that an object has due to its motion.

• Energy that is created by a rolling marble.

• Energy that is converted from motion.

Multiple Choice

What happens to a marble's energy as it begins to roll down a ramp?

• The marble’s potential energy is converted into kinetic energy.

• The marble’s kinetic energy is converted into potential energy.

• The marble loses all of its energy as it rolls down.

• The marble only has potential energy while it is rolling.

Multiple Choice

A marble is sitting motionless at the top of a hill. Which statement provides the best conclusion about its energy?

• It has stored potential energy but no kinetic energy.

• It has kinetic energy but no potential energy.

• It has neither potential nor kinetic energy.

• It has equal amounts of potential and kinetic energy.

Factors Affecting Potential Energy

• An object's height determines its potential energy.

• An object's mass also affects its potential energy.

• This stored energy converts into energy of motion.

Multiple Choice

Which two factors determine an object's potential energy?

• Its height and its mass

• Its speed and its direction

• Its color and its shape

• Its temperature and its texture

Multiple Choice

What is the relationship between an object's height and its potential energy?

• Its potential energy increases.

• Its potential energy decreases.

• Its potential energy stays the same.

• Its potential energy is converted to motion.

Multiple Choice

A basketball is held at the top of a ramp. What can be concluded about the energy it will have as it rolls down the ramp?

• The basketball's stored energy will be converted into energy of motion.

• The basketball will lose all its energy as it rolls down.

• The basketball's energy of motion will be converted into stored energy.

• The basketball will have no energy at the bottom of the ramp.

​

​

Kinetic Energy, Mass, and Speed

Relationship with Mass

Relationship with Speed

Multiple Choice

What type of relationship exists between an object's kinetic energy and its mass when its speed is held constant?

• A linear relationship, where kinetic energy increases directly with mass.

• A squared relationship, where kinetic energy increases exponentially with mass.

• An inverse relationship, where kinetic energy decreases as mass increases.

• No relationship, as mass does not affect kinetic energy.

Multiple Choice

Which statement best compares the effects of changing an object's mass versus changing its speed?

• Doubling the speed has a greater effect on kinetic energy than doubling the mass.

• Doubling the mass has a greater effect on kinetic energy than doubling the speed.

• Mass and speed have an equal, linear effect on kinetic energy.

• Only an object's speed affects its kinetic energy, not its mass.

Multiple Choice

If a scientist were to plot the data for a moving object on two different graphs, what would the graphs of 'kinetic energy vs. mass' and 'kinetic energy vs. speed' look like?

• The mass graph would be a straight, upward-sloping line, while the speed graph would be a steeply rising curve.

• The speed graph would be a straight, upward-sloping line, while the mass graph would be a steeply rising curve.

• Both graphs would be straight, upward-sloping lines.

• Both graphs would be steeply rising curves.

Energy Transfer: Collisions and Friction

• A moving object transfers kinetic energy to a stationary object upon collision.

• Friction between the sliding object and the surface resists motion.

• This friction converts kinetic energy into thermal energy, stopping the object.

Multiple Choice

What happens when a moving object collides with a stationary object?

• Kinetic energy is transferred to the stationary object.

• Thermal energy is created from nothing.

• The stationary object develops friction instantly.

• The moving object gains more kinetic energy.

Multiple Choice

What is the role of friction as an object slides across a surface?

• It converts kinetic energy into thermal energy.

• It increases the object's speed and momentum.

• It eliminates the transfer of energy during a collision.

• It transforms thermal energy back into kinetic energy.

Multiple Choice

If two identical objects are sliding on two different surfaces with the same initial speed, what is the best prediction for their motion?

• The object with more friction will stop sooner because its kinetic energy is converted to thermal energy more quickly.

• The object with less friction will stop sooner because it transfers less kinetic energy upon collision.

• Both objects will stop at the same time because they started with the same energy.

• The object with more friction will travel farther because friction adds energy to the system.

​

Common Misconceptions

​

Summary

Poll

How confident are you with the concepts of potential and kinetic energy after this review?

• 1 - Not confident

• 2 - A little confident

• 3 - Mostly confident

• 4 - Very confident