Question

.A car is travelling at a speed of 108 km h 1. Acceleration produced in the opposite
direction of motion on applying brakes to the car is 2.5 ms.
[3]
(i) After how many seconds will the car stop?
(ii) How much distance is travelled by the car before it comes to rest ?​

Answer 1

Answer:

108km/h×5/18=30m/s.

speed of brakes(in opposite direction)= 2.5m/s^2(meter per second square)

(i) Time taken to stop the car = 30m/s / 2.5m/s^2

=12 seconds.

(ii) Distance travelled before stopping = 30×2.5

=75m.

Answer 2

Answer:

(i) t=18seconds

(ii) s= 4590 meters

Explanation:

u= 108 kmph= 30mps

a = 2.5m/s^2

v-u/t=a

0-30/t=2.5

t= -30*10/25

t= 18s

s= ut + 1/2at^2

s= 30*18+1/2*25/10*18*18

s= 4590 meters