Question

A motor car moving with a uniform speed of 20m/sec
comes to stop on the application of brakes after travelling
distance of 10m its acceleration is

Answer 1

Feel free to correct me.

V=0

U=20m/s

S=10m

Hence, Newton's equation...

V^2= U^2+2as

20^2= -2(10)a

a= 400/-20

a= -20m/s^2

Answer 2

Answer:

Acceleration of the motor car, a = -20 m/s²

Explanation:

It is given that,

The motor car is moving with a speed of 20 m/s i.e. u = 20 m/s. Finally it comes to rest i.e. v = 0. Distance travelled before coming to rest is 10 m.

We have to find the acceleration of the motor car. It is defined as the rate of change of velocity. This can be obtained by  using third equation of motion as :

$v^2-u^2=2as$

$(0)^2-(20\ m/s)^2=2a\times 10\ m$

$a=-20\ m/s^2$

So, the retardation produced by the motor car is 20 m/s². Hence, this is the required solution.