Question

 A car is travelling at a speed of 90 km/h .Brakes are applied so as to produce a uniform acceleration of -0.5 m per second square.Find how far the car will go before it is brought to rest?​

Answer 1

Answer:

625 metres

Explanation:

Given:

Initial velocity = 90 km/h = $90 \times \frac{5}{18}$ = $25 m/s$ (u)

Acceleration = -0.5 m/s² (a)

Final velocity = 0 m/s (As the car would finally come to rest) (v)

To find:

Distance travelled by the car before coming to rest (s)

Using third equation of motion which says :

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

Substituting the values, we get:

$0^{2} -25^{2} =2 \times -0.5 \times s$

$0-625= -1s$

$-625 = -1s$

$s = \frac{-625}{-1}$

$s = 625 m$

The bus will travel 625 metres before coming to rest

Answer 2

Answer:

625 m

it is the correct answer