11. Which of these is an example of converting gravitational potential energy to kinetic energy? A. a person running on a level track
B. an apple falling from a tree to the ground
C. a rope spring that makes a toy car move across the ground
D. a rubber band stretches twice as long normal length

this could be newton#'s law of cooling. the cooling curve is exponential

so easy. just google the electromagnetic waves and it’ll pop up.

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.