1. In studying the behavior of bouncing balls, a couple of Science 10 students recorded the following energy values.
Bouncing Balls
Type of Ball
Starting Potential Energy (J) Ending Potential Energy (J)
golf ball
0.44
0.38
tennis ball
0.56
0.30
Use these energy values to compare the percent efficiencies of the balls during the bounce.

when insulating materials rub against each other, they may become electrically charged . electrons , which are negatively charged, may be 'rubbed off' one material and on to the other. the material that gains electrons becomes negatively charged. the material that loses electrons is left with a positive charge.

answer:   you might love summer weather, but you don’t want it to feel like the sun is inside your car. but a hot car that just won’t seem to cool down might be a bigger of a problem than you think. your car relies on being at the right temperature.

explanation:

the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.

there are no contact forces mentioned on the list of choices that you've provided.