Question

a vehicle was moving at a speed of 90km/h on seeing a baby 20 m ahead on the road , the driver jammed on the brakes and it came to rest at a distance of 15m . what is its retardation and how long does it take to come at rest ? site:brainly.in​

Answer 1

Answer:

v = 0

u = 90 km/hr = 25m/s

s = 15 m

a = ?

by using third equation of motion

v² = u² + 2as

0² = 25² + 2(a)15

0 = 625 + 30a

-625 = 30a

a = -625/30

a = - 20.84 m/s² (approx)

ExplanatioN

by putting the values in formula it is very easy