Question

State the law of conservation of momentum. Express it mathematically. Two balls of masses 100 g and 200 g moving in the same direction with velocities 2 ms-1 and 1 ms-1 respectively collide with each other. If the velocity of the ball of mass 200 g after collision becomes 1.165 ms-1, find the velocity of the other ball.

Answer 1

Law of conservation of momentum
The law of conservation of momentum states that the total momentum of a closed system does not change. This means that when two objects collide then the total momentum before collision is equal to the total momentum after collision.

Given:
m1 = 100g = 0.1kg     u1 = 2m/s         v1 = ?
m2 = 200g = 0.2 kg    u2 = 1m/s        v2 = 1.165m/s
by using law of conservation of momentum, 
m1u1 + m2u2 = m1v1 + m2v2
0.1 × 2 + 0.2 × 1 = 0.1 × v1 + 0.2 × 1.165
0.2 + 0.2 = 0.1v1 + 0.233
0.4 = 0.1v1 + 0.233
0.1v1 = 0.4 - 0.233
0.1 v1 = 0.167
or v1 = 1.67 m/s

Answer 2

Answer:

The law of conservation of momentum states that the total momentum of a closed system does not change. ... F = ma , acceleration is change is velocity over time.. so F = m [ (v1-v2)/t] , F = (mv1 -mv2) /t , Now mv = momentum so F = (momentum 1 - momentum2)/t ...