Which came first: the chicken or the egg? One might ask the same question about potential and kinetic energy. Make observations while you watch the video below. Think about what scientific conclusion you could make from your observations. Be ready to supply an explanation!
Engage: The Great Egg Drop
Explore I: Energy Makes a Splash
You just observed eggs falling from different heights. What about that all-familiar liquid, water? Do you think what you observed would be true with water as well? The Explore Student Version document in the Related Items section below may help you discover your own unique answer to that question.
Explain I: Thinking through Science
How do you think the experiences in the Engage and Explore apply to the following science terms?
Potential Energy: stored energy, such as energy of position, that, when released, results in movement of an object or the increased motion of the particles that make up an object
Kinetic Energy: energy of motion, when an object or the particles that make up an object are in motion
At what point did the egg have the most potential energy? The most kinetic energy? Does an increased amount of potential energy have an influence on an object's kinetic energy?
Look at the animation below. Notice that it has a circle graph. This circle graph gives you information on how much potential and kinetic energy are present at any given point on the roller coaster's track. Do two investigations using the animation.
- Use the PLAY button on the animation to determine where a roller coaster has its greatest amount of potential energy and where it has the greatest amount of kinetic energy.
- Use the STEP button to freeze-frame the roller coaster at specific points. Is there a relationship between potential energy and kinetic energy? If so, what is that relationship? Observe the velocity (speed in a given direction) of the roller coaster at each point. What pattern, if any, do you notice?
Explore/Explain II: Science through Singing
Are potential and kinetic energy just about the height of an object? If you asked the average person, he or she would most likely say that an object has more kinetic energy the higher off the ground the object is. Watch the video below and make observations about potential and kinetic energy examples that don't involve how high something is. Record in your science journal the other examples of potential and kinetic energy from the video. Compare and contrast potential and kinetic energy. In what ways are they the same and in what ways are they different?
Elaborate: Energy Challenge!
Given all that you know now about potential and kinetic energy, consider the following question.
How can you throw a ball and have its energy change from kinetic to potential and back to kinetic without touching the ball once you release it from your hand?
Draw a diagram along with your explanation and label it to demonstrate where energy changes from kinetic to potential and back to kinetic. Good luck!