Question

Two hockey play
opposite teams, while trying to hit
hockey ball on the ground collide
. One
immediately become entangled.
has a mass of 60 kg and was moving
with a velocity 5.0 m s-1 while the other
has a mass of 55 kg and was moving
faster with a velocity 6.0 m s-l towards
the first player. In which direction and
with what velocity will they move after
they become entangled? Assume that
the frictional force acting between the
feet of the two players and ground
negligible..​

Answer 1

Given - m1 = 60 kg , u1 = 5m/s(left to right direction) , m2 = 55kg , u2 = -6m/s ( because the two players are moving in opposite directions i.e. the second from right to left )

Total momentum of the two players before collision = m1 u1 + m2 u2 = 60 (5) + 55 (-6)

= 300 + (-330)

= -30 kgm/s

Total momentum of the two players after collision = (m1 + m2 )v

Where v will be the velocity of the two players after collision

By law of conservation of momentum,

-30 kgm/s = (m1 + m2 )v

-30 = (60 +55) v

v = - 30/115

=- 0.26m/s

Thus,the velocit y of the players will be 0.26m/s in the direction of the second player i.e. from right to left.