Question

Two cars moving in same direction have velocity u and 4u at some time. From this time, car possesses retardation and brought to rest, after applying brakes then what is ratio of distances travelled by them?​

Answer 1

Answer:

By Newton's third law of motion

v

2

−u

2

=2as

here acceleration a is negative since it is retardation, displacement s is the stopping distance d, u is the initial velocity and v is the final velocity.

Since the objects tops after the motion, v=0

thus

−u

2

=−2ad

d=

2a

u

Let take d

1

as the distance traveled by the car with velocity u and d

2

as the distance traveled by the car with velocity 4u.

The retardation for both the car is −a

d

2

d

1

=

2a

u

2

(4u)

2

2a

d

2

d

1

=

16

1