Energy Questions

1) If someone says a donut “has 450 calories” what are they really saying (whether they know it or not)?

2) The scientific use of the word work is different from the common use of the word. A force is required to do work. What else needs to happen?

3) Let’s say you walk up a hill, and later you run up the same hill. Which of these requires more energy? Which requires more power? Please explain you r answer to the second question using the equation for power.

4) A basketball player leaps straight up into the air. Where is her gravitational potential energy the greatest? Where is her kinetic energy the greatest?

5) What kind of energy does light have?

6) Put positive and negative charges near each other and they try to pull together. If you hold them apart and don’t let them come together, what kind of energy do they have?

7) Imagine you are driving in a car that makes a sudden stop. What kind of energy did the car have while it was moving? Where is this energy after the car stops, and what kind of energy is it?

8) An apple hanging from a tree has gravitational potential energy. As it is falling, what happens to the potential energy? Where does the energy go after the apple hits the ground?

9) Does a laptop computer wear out its batteries faster if its screen is brighter? Explain carefully, and make sure you include the concepts of work and power in your answer.

10) Rubbing your hands together makes them warmer. Higher temperature means more energy, so where was the potential energy before it warmed your hands? What type of potential energy was it?

11) Is it correct to say that an object “has energy”? Is it correct to say that an object “has work”?

12) What kind of energy is solar energy?

13) Two friends are arguing about roller coasters. The first friend says the first hill must be highest, and each hill must be lower than the hill before it because of friction. The second friend says that’s wrong, and as long as the first hill is highest it doesn’t matter what height the others are. Who is right? Please explain.