Question

A driver of a car travelling at 72 km/h applies the brakes and accelerates
uniformly in the opposite direction. The car stops in 5secs. Another driver
going at 36 km/h in another car applies his brakes slowly and stops in 10
secs. Which of the two cars travelled farther after the brakes were applied?

Answer 1

please refer the attachment for for better understanding

Car A

initial velocity ( u)=72 km/hr=72×5/18=20m/s

time taken (t)=5 sec

final velocity (v)=0

the distance covered by the car B is equals to the area under ∆ABC

=1/2×base×height

=1/2×5×20

=50m

Car B

initial initial velocity (u)=36km/hr=36×5/18=10m/s

time taken (t)=10 sec

final velocity (v)=0

distance covered by car Bequals to the area under ∆DBE

=1/2×10×10

=50 m

both cars travel equal distances before the break were applied

I hope this helps ( ╹▽╹ )