Question

a bus is moving with an initial velocity 'u' m/s. and is stopped after 12s. find the initial velocity 'u' and distance travelled by the bus after applying brakes ?​

Answer 1

S O L U T I O N :

Given,

• Time (t) = 12 s
• Final velocity (v) = 0 m/s

To Find,

1. Initial velocity of the bus.
2. Distance travelled by the bus after applying brakes.

Explanation,

(1) Initial velocity of the bus.

Applying newton's 1st equation of motion,

v = u ± at

[In the case the the breaks are applied, hence the accelaration will be taken as negative]

v = u - at

=> 0 = u - 12a

=> - u = -12a

=> u = 12 a

(2) Distance travelled by the bus after applying brakes.

Applying newton's 3rd equation of motion,

v² = u² - 2aS

=> -u² = - 2aS

=> (12a)² = 2as

=> 144a² = 2as

=> 72a = s

=> s = 72a