Question

A car moves with uniform retardation.If the car covers 40 m in last two seconds of it's motion,what is the velocity of the car at the beginning of the last second.​

Answer 1

Consider velocity before 2 secs and 1 sec before rest as v2 and v1 respectively. Let retardation be ‘-i’.

By equations of motion,

s=ut + 1/2at²,

So, 40=v2(2)- 1/2i(4)

v2 - i=20….(eqn 1)

Also,

v=u+at,

So, 1sec before rest,

v1=v2-i(1)

From eqn 1,

v1= 20m/sec.-answer.

Hope its helpful..

Answer 2

Answer:

Explanation:

Hope it will make you understand