A collision occurs between two pucks on an air-hockey table. Puck A has a mass of 0.020 kg and is moving along the x axis with a velocity of +5.5 m/s. It makes a collision with puck B, which has a mass of 0.040 kg and is initially at rest. The collision is not head-on. After the collision, the two pucks fly apart with puck A 65º above the x-axis and puck B 37º below the x-axis.

Question

(a) Find the final speed of puck A.

(b) Find the final speed of puck B.

Answer 1

Use conservation of momentum.

In the x direction:

0.02*5.5 = 0.02*vA*cos(65) + 0.04*vB*cos(37)

In the y direction:

0 = 0.02*vA*sin(65) - 0.02*vB*sin(37)

You should be able to use algebra to solve for these equations, since you have two equations with 2 unknowns; vA is the final speed of puck A; vB is the final speed of puck B

Answer 2

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