Question

A stone falls freely under gravity. It covers distances h1, h2and h3 in the first 5 seconds, the next 5 seconds and the next 5 seconds respectively. The relation between h1, h2 and h3 is

(a) h2 = 3h1 and h3 = 3h2

(b) h1= h2= h3

(c) h1= 2h2 = 3h3

(d) h1 = h2/3 = h3/5

Answer 1

Correct option**(d) h1 = h2/3 = h3/5**

Explanation:

Distance covered by the stone in first 5 seconds

(i.e. t = 5 *) is

h1 = 1/2g(5)2 = 25/2g

Distance travelled by the stone in next 5 seconds

(i.e. t = 10 *) is

h1 + h2 = 1/2g(10)2 = 100/g

Distance travelled by the stone in next 5 seconds

(i.e. t = 15 *) is

From (i), (iv) and (v), we get

h1 = h2/3 = h3/5