Question #b6c63

1 Answer
Dec 17, 2016

There appears to be some missing text in the opening sentence of the question.

Assuming it is as follows:

"A golf ball collides elastically with a bowling ball initially at rest and bounces back."

It is given that the golf ball bounces back with tiny loss in its incident speed.

Let #m_g# be mass of golf ball and #v_i# be its initial velocity. Let #M_b# be the mass of bowling ball. And #p_b# be final momentum of bowling ball.
Initial momentum of the system is
#p_i=m_gxxv_i+M_bxx0#
#=>p_i=m_gv_i# .......(1)

Final momentum #p_f# is
#p_f=m_gxx(-v_i)+p_b#
#=>p_f=-m_gv_i+p_b# .....(2)

Using law of conservation of momentum, we equate (1) with (2). We get
#m_gv_i=-m_gv_i+p_b#
#=>p_b=2(m_gv_i)# ....(3)

We see that after collision, bowling ball recoils with twice the initial momentum of golf ball.