Question

When a car driver travelling at a speed of 10 m/s applies brakes and brings the car to rest in 20 s, then the retardation will be *

:(a) + 2 m/s2
(b) − 2 m/s2
(c) − 0.5 m/s2
(d) + 0.5 m/s2​

Answer 1

Answer:

(c)-0.5m/s^2

Explanation:

given,

u=10m/s

v=0m/s

t=20s

by first equation of motion

v=u+at

put the values of u,v and t in the equation

0=10+a×20

0-10=20a

-10/20=a

-1/2=a

a= -0.5m/s^2