Question

two balls of mass gm and 100gm are moving along same line in same direction with 3m/s and 1.5m/s respectively. They collide and return back. If the velocity of first ball is 2.5m/s then find the velocity of the second ball.

Answer 1

Answer:

Correct option is

C

1.33 m/s

Given : m

1

=m

2

=0.1 kg

Velocities of objects before collision : u

1

=2 m/s u

2

=1 m/s

Velocities of objects after collision : v

1

=1.67 m/s v

2

=?

Conservation of momentum : P

i

=P

f

∴ m

1

u

1

+m

2

u

2

=m

1

v

1

+m

2

v

2

OR 0.1(2)+0.1(1)=0.1(1.67)+0.1v

2

⟹v

2

=1.33 m/s