Question

19. A copper ball of radius 8 cm is initially at rest on a horizontal frictionless surface. It is struck head on by another steel ball of radius 4 cm and moving with a velocity of 9 m/s. Calculate the velocities of the two balls after collision.​

Answer 1

Answer:

Correct option is

C

144cm/s and 63cm/s

radii give us their masses:8m and m

u

1

=81cm/s;u

2

=0

v

1

=(m

2

−m

1

)u

1

/(m

2

+m

1

);v

2

=(2m

1

)u

1

/(m

2

+m

1

)

v

1

=7mu/9m=9∗81/9=63cm/s;v

2

=16∗81/9=144cm/s