Question

A book is dropped from the top of a 32.0 m high building. A marker is dropped 2.00 s later. How high above the ground is the marker when the book hits the ground?

a) 10.8 m
b) 16.0 m
c) 21.2 m
d) 26.4 m

Answer 1

The marker is 3.21 meters above the ground when the book hits the ground.

Step-by-step explanation:

To find the height above the ground at which the marker is when the book hits the ground, we need to determine the time it takes for the book to hit the ground. Since the book is dropped from rest, we can use the formula h = (1/2)gt^2, where h is the height, g is the acceleration due to gravity (9.8 m/s^2), and t is the time. Using this formula, we can calculate that it takes the book about 2.83 seconds to hit the ground. Therefore, the marker has been falling for 2.83 - 2.00 = 0.83 seconds. Using the same formula and plugging in this time, we can find that the height of the marker above the ground is (1/2)(9.8)(0.83)^2 = 3.21 meters. Therefore, the marker is 3.21 meters above the ground when the book hits the ground.