A boulder is dropped from a cliff.A second boulder is dropped from a cliff that is half as high.How does the speed of the second boulder upon impact compare with that of the first?
A)Ths speed of the second is approximately 0.5 times the speed of the first.
B)Ths speed of the second is approximately 0.7 times the speed of the first.
C)Ths speed of the second is approximately 0.25 times the speed of the first.
D)Ths speed of the second is approximately 2 times the speed of the first.
E)Ths speed of the second is approximately the same as the speed of the first.

Question

Quizplus · Accepted Answer

The speed of an object in free fall from a certain height is determined by the square root of that height (given constant acceleration due to gravity). Therefore, if the second boulder is dropped from a height that is half of the first, its speed upon impact will be the square root of 0.5 (or 1/2), which is approximately 0.7 times the speed of the first boulder.

A Boulder Is Dropped from a Cliff