Question

A 70.0 kg ice hockey goalie, originally at rest, has a 0.110 kg hockey puck slapped at him at a velocity of 43.5 m / s . Suppose the goalie and the puck have an elastic collision, and the puck is reflected back in the direction from which it came. What would the final velocities of the goalie and the puck be in this case

Answer 1

Answer:

0.06824 m.s for each  - puck and goalie

Explanation:

Mass of puck=m1= 0.11 kg

Mass of goalie = m2 = 70 kg

Initial vel of puck=V1i= 43.5 m/s

Initial vel of goalie = Vi2= 0 m/s

V1f = final velocity of puck

Vf2= final velocity of goalie

Because goalie hits the puck , the final velocity of both is equale i-e Vf1=Vf2=V

Using constant momentum rule;

m1V1i+m2V2i = m1 V1f+m2V2f

==> m1 V1i +0 = m1 V1f+m2V2f

==>m1 V1i  = (m1+m2) V

==> V= m1V1i ÷ (m1+m2) = 0.11 × 43.5 ÷ (0.11+70)= 4.785÷ 70.11 m/s = 0.06824 m/s