JEE Main Physics Class 11 Motion in a Straight Line and Plane Part 1 Questions

Using equation, a=

v−u

t

and S=ut+

1

2

at2
Distance travelled by car in 15 sec =

1

2

(45)

15

(15)2 =

675

2

m
Distance travelled by scooter in 15 seconds = 30 × 15 = 450
(∵ distance = speed × time)
Difference between distance travelled by car and scooter in 15 sec, 450 – 337.5 = 112.5 m
Let car catches scooter in time t;

675

2

+45(t−15)=30t
⇒337.5+45t−675=30t
⇒15t=337.5
⇒t=22.5‌sec