Question

Two steal balls a and b of mass 10 kg and 10 grams rose towards each other with 5 and 1 metre per second respectively on a smooth 4 after collision

Answer 1

Mass of ball A = 10 kg

Velocity = V1 = 5 m/s

Mass of ball B = 10 g = 10/1000 = 0.01 kg

Velocity = V2 = 1 m/s

Momentum of ball A before collision = (10) (5) = 50 kg m/s

Momentum of ball B before collision = (0.01) (1) = 0.01 kg m/s

Total momentum before collision = 50 + 0.01 = 50.01 kg m/s

Since momentum is conserved, So total momentum after collision must be equal to 50.01 kg m/s

Now,

Total mass = Mass of ball A = Mass of ball B

Total mass = 10 + 0.01 = 10.01 kg

For velocity,

p = m v

v = p/m

v = 50.01/10.01

v = 4.99 m/s or 5 m/s