Question

A bus was moving with a speed of 54km/h. On applying brakes, it stopped in 5 seconds.

Calculate (a) the acceleration and (b) distance travelled before stopping.​

Answer 1

Answer:

a) the acceleration

it is correct answer

Answer 2

Given :-

A bus was moving with a speed of 54km/h. On applying brakes, it stopped in 5 seconds.

To Find :-

Calculate (a) the acceleration and (b) distance travelled before stopping.​

Solution :-

We know that

1 km/h = 5/18 m/s

54 km/h = 54 × 5/18 = 15 m/s

a = v - u/t

a = 0 - 15/5

a = -15/5

a = -3 m/s²

Now

v² - u² = 2as

(0)² - (15)² = 2(-3)(s)

0 - 225 = -6s

-225 = -6s

s = -225/-6

s = 37.5 m