Question

A disk A of radius r moving on a perfectly smooth surface at a speed v undergoes an elastic collision with
an identical stationary disk B. Find the velocity of the disk A after a collision if the impact parameter is r/2
as shown in the figure.
A.
V
r/2​

Answer 1

A disk A of radius r moving on a perfectly smooth surface at a speed v undergoes an elastic collision with

an identical stationary disk B. Find the velocity of the disk A after a collision if the impact parameter is r/2

as shown in the figure.

A.

V

r/2​

Explanation:

Let V1 and V2 be the final velocity after collision of disk A and disk B respectively.

Applying principles of conservation of linear momentum.

From fig 2 sin x = r/2 ÷2r=

1/4

Cos x=√15/4

We know that m=m

The rest of the solution is attached in the image.