A 0.115 kg hockey puck, moving at 35.0 m/s, strikes a 0.265 kg octopus thrown onto the ice by a hockey fan. The puck and the octopus slide off together. Find their velocity.

Velocity of puck and the octopus is 10.59 m/s.

Explanation:

Here momentum is conserved.

Initial momentum = Final momentum.

Initial momentum = Momentum of hockey puck

Mass of hockey puck = 0.115 kg

Velocity of hockey puck = 35 m/s

Initial momentum = 0.115 x 35 = 4.025 kg m/s

Final momentum = Momentum of puck and the octopus

Combined mass = 0.115 + 0.265 = 0.38 kg

Let v be the speed.

Final momentum = 0.38 x v = 0.38 v

We have

4.025 = 0.38v

v = 10.59 m/s

Velocity of puck and the octopus is 10.59 m/s.