Question

A body falls freely from the rest. It covers as much distance in the last second of its
motion as covered in first three seconds. The body has fallen for a time of:please answer using Sn=u+a/2(2n-1)​

Answer 1

Answer:

5 sec

Explanation:

Displacement in nth sec of the free fall s

Snth = 1/2g (t1²-t2²)

given: (tn -tn-1)=1

displacement in 3 second of the free fall

S= 1/2 gt²

S= 1/2×10×3²

S= 45 m

Given that: Snth=45

on solving that we get

t1=5 sec