Question

when a car driver travelling at a speed of 10 km per second applies break and bring the car to the rest in 20 seconds then the retardation will be​

Answer 1

Given:

• Initial velocity, u = 10 m/s

• Final velocity,,v = 0 m/s

• Time taken = 20 second

To be calculated:

Calculate the retardation ( negative acceleration) ?

Formula used:

Acceleration = v - u / t

Solution:

We know that,

Acceleration = v - u / t

Substituting the values in the above formula, we get

Acceleration = 0 - 10 / 20

= -10 / 20

= -1 / 2

= -0.5 m/s²

Thus, the acceleration of the car is - 0.5 m/s². it is negative in sign ,but the negative acceleration is known as retardation.