What is the final velocity in the following scenario?

A body of mass 16 kg travelling to the right at 5 m/s collides with a body of mass 4 kg travelling to the left at 5 m/s. After collision the two bodies stick together.

Expert Answers

An illustration of the letter 'A' in a speech bubbles

In a perfectly inelastic collision:

M1*v1 + M2*v2 = (M1 + M2)*vf

Here M1 and M2 are the masses of the bodies colliding, v1 and v2 are their initial velocity and vf is their final velocity.

Now, in the problem it is given that the body of mass 16 kg is travelling at 5 m/s towards the right. It collides with a body of mass 4 kg travelling at 5 m/s towards the rest.

Therefore we can use

M1*v1 + M2*v2 = (M1 + M2)*vf

=> vf = (M1*v1 + M2*v2)/(M1 + M2)

=> vf = (16*5 - 4*5)/20

=> vf = 60/20

=> vf = 3 m/s

The final body made up of the bodies that collided with each other moves at 3 m/s towards the right.

See eNotes Ad-Free

Start your 48-hour free trial to get access to more than 30,000 additional guides and more than 350,000 Homework Help questions answered by our experts.

Get 48 Hours Free Access
Approved by eNotes Editorial