1

Question

A car weighing 1000 kg collides with a stationary 50 kg trolley, and imparts a velocity of 75 msâˆ’1 to it. Find the speed with which the car was moving (Assume that the car comes to a stop after the collision and neglect friction at the time of collision).

Open in App

Solution

The correct option is **C** 4.25 ms−1

Let the initial velocity and final velocity of the car be U,V respectively.

Let the initial velocity and final velocity of the trolley be u,v respectively.

Given: Mass of car, M=1000 kg, mass of trolley, m=50 kg, v=75 ms−1

Initial momentum of car =MV

Initial momentum of trolley, mu=0 (initially at rest)

Final momentum of car, MU=0 (comes to rest after collision)

Final momentum of trolley =mv

Using the law of conservation of momentum:

Toatal initial momentum of system = Total final momentum of system

⇒MV+0=0+mv⇒MV = mv

⇒V=mvM=50×751000=3.75 ms−1

Therefore the initial velocity of car, V=3.75 ms−1

Let the initial velocity and final velocity of the car be U,V respectively.

Let the initial velocity and final velocity of the trolley be u,v respectively.

Given: Mass of car, M=1000 kg, mass of trolley, m=50 kg, v=75 ms−1

Initial momentum of car =MV

Initial momentum of trolley, mu=0 (initially at rest)

Final momentum of car, MU=0 (comes to rest after collision)

Final momentum of trolley =mv

Using the law of conservation of momentum:

Toatal initial momentum of system = Total final momentum of system

⇒MV+0=0+mv⇒MV = mv

⇒V=mvM=50×751000=3.75 ms−1

Therefore the initial velocity of car, V=3.75 ms−1

1

View More

Join BYJU'S Learning Program

Join BYJU'S Learning Program