Question

A ball moving with a velocity of 6 m/s strikes an idemi!
stationary ball. After collision each ball moves at aii of
30° with the original line of motion. Assuming that'
collision is elastic, What are the speeds of the balls M
the collision ?
a)
və
m/s, 273 m/s b) 3m/s, 273 m/s
c) 213 m/s, 213 m/s d) 13 m/s, 13 m/s​

Answer 1

Answer:

Let the mass of the balls be ‘m’.

Before collision net momentum along X axis is = 9m

Before momentum net momentum along Y axis is = 0

After collision, let the velocities of the balls be v1 and v2.

So, after collision the momentum along X axis is = mv1 cos30 + mv2 cos30

And the momentum along Y axis is = mv1 sin30 - mv2 sin30

Now, applying law of conservation of momentum,

mv1 cos30 + mv2 cos30 = 9m

=> v1 + v2 = 9/(cos30) = 10.39 ………..(1)

And,

mv1 sin30 - mv2 sin30 = 0

=> v1 = v2 …………(2)

Using, (1) and (2),

v1 = v2 = 10.39/2 ≈ 5.2 m/s