Question

A body moving with a velocity of 20m/s is brought down to rest after 40m. find the time taken by the body to come down to rest.​

Answer 1

Answer:

V(t)=Vo+at

V(t) final velocity; Vo initial velocity;

a acceleration; t time

Vo=20 m/sec

t=5 sec

V(t)=0

Hence 0=20+5a

Solving for a we get:

a=-4 m/sec^2

Answer 2

Answer:

Initial velocity =40m/s

Final velocity =0 m/s

Time taken =5 sec

We know

V=U+AT

0=40+A×5

A= - 8

Retardation =8 m/s²

Here negative sign indicates Retardation