Question

A bored college student on top of a 6-story tall building drops a water balloon on his friends directly below. In one second it falls one story down from the top. In one more second it will be:
a Two stories below the top.
b Three stories below the top
c Four stories below the top.
d none of the above

Answer 1

Answer:

c Four stories below the top.

Explanation:

t = Time taken

u = Initial velocity

s = Displacement

a = Acceleration

g = Acceleration due to gravity = 9.81 m/s² = a

$s=ut+\dfrac{1}{2}at^2\\\Rightarrow s_1=0\times t+\dfrac{1}{2}\times g\times 1^2\\\Rightarrow s_1=0.5g\ m$

In two seconds

$s_2=0\times t+\dfrac{1}{2}\times g\times 2^2\\\Rightarrow s_2=4\times 0.5g\\\Rightarrow s_2=4s_1$

So, in two seconds the water balloon will fall 4 stories below the top