Question

A 25 kg rock falls for 2.7 seconds. How many meters tall was the building?

Answer 1

Answer:

35.7m

Explanation:

Given parameters:

Mass of rock  = 25kg

Time of fall  = 2.7s

Unknown:

Height of the building = ?

Solution:

To solve this problem, we will use one of the motion equations;

     S  = ut + $\frac{1}{2}$ gt²

S is the height

u is the initial velocity  = 0m/s

t is the time

g is the acceleration due to gravity

      S = (0 x 2.7) +  $\frac{1}{2}$ x 9.8 x 2.7²  = 35.7m