What is the final velocity of the goalie after catching a hockey puck?

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The discussion centers on calculating the final velocity of a goalie after catching a hockey puck using the principle of conservation of momentum. A 0.105-kg puck moving at 20 m/s is caught by a 77-kg goalie initially at rest. The relevant equation is m1v1 + m2v2 = (m1 + m2)v', where m1 is the puck's mass, v1 is its velocity, m2 is the goalie's mass, and v' is their combined final velocity. The solution involves solving for v' to determine how fast the goalie slides on the ice after the collision. The importance of using the correct initial conditions in the momentum equation is emphasized for accurate results.
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Homework Statement



A 0.105-kg hockey puck moving at 20 m/s is caught and held by a 77-kg goalie at rest. With what speed does the goalie slide on the ice?


Homework Equations



(Initial puck speed)(Puck mass)
= (combined mass)*(final goalie velocity)

The Attempt at a Solution


(0)(0.105)=(77.105)(20)
= 1542.1 m/s
 
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wesDOT is correct. Initial velocity of the puck should not be zero.

To cross-post from the other thread about two cars colliding inelastically:

Re: Two objects colliding & sticking together said:
The main thing you can use in the problem is conservation of momentum:

m1v1+m2v2=(m1+m2)v'

This equality is a result of the completely inelastic collision. The question asks you to solve for v'.

m1 : mass of the puck
v1 : initial velocity of the puck
m2 : mass of the goalie
v2 : initial velocity of the goalie
v' : final velocity of the puck+goalie

Hope this helped.
 
oops, double posted. sorry. & that was correct, thanks!
 

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