What Are the Final Velocities of Hockey Pucks After a Glancing Collision?

[member_216668]

Homework Statement

Two equal mass hockey pucks undergo a glancing collision. Puck 1 is initially at rest and is struck by puck 2 traveling at a velocity of 13 m/s[E]. Puck 1 travels at an angle of [E18N] after the collision. Puck 2 travels at an angle of [E4S]. Determine the final velocity of each puck.

How do I solve the problem using conservation of momentum since I only have the two initial velocities?

Homework Equations

p=mv
mv₁+mv₂ = mv_1f+mv_2f

The Attempt at a Solution

I've tried to use the equations for a perfectly elastic collision

 

[Isaac0427]

If they have equal masses, shouldn't puck 2 have a velocity of 0 and not move in any direction? I'm not sure but that is how I learned the conservation of momentum.

 

[member_216668]

Well puck 1 has a velocity of zero and puck 2 strikes it, so in the conservation of momentum equation, v₁ cancels out along with all the masses. The equation then becomes v₂ = v_1f + v_2f. With that equation there's two unknown values and one known, so I'm not sure how to solve it from this point on.

 

[SammyS]

If they have equal masses, shouldn't puck 2 have a velocity of 0 and not move in any direction? I'm not sure but that is how I learned the conservation of momentum.

That's only if it's a head-on elastic collision. This is a glancing collision.

 

[Ray Vickson]

Homework Statement

Two equal mass hockey pucks undergo a glancing collision. Puck 1 is initially at rest and is struck by puck 2 traveling at a velocity of 13 m/s[E]. Puck 1 travels at an angle of [E18N] after the collision. Puck 2 travels at an angle of [E4S]. Determine the final velocity of each puck.

How do I solve the problem using conservation of momentum since I only have the two initial velocities?

Homework Equations

p=mv
mv₁+mv₂ = mv_1f+mv_2f

The Attempt at a Solution

I've tried to use the equations for a perfectly elastic collision

What does angle [E18N] mean? Is it 18 degrees north of east? Is is 18 degrees east of north? Is it something else?