Question

Two hockey pucks with mass 0.1 kg slide across the ice and collide. Before

the collision, puck 1 is going 15 m/s to the east and puck 2 is going 12 m/s to
the west. After the collision, puck 2 is going 15 m/s to the east. What is the
velocity of puck 1?

Answer 1

12 m/s west

Step-by-step explanation:

just did it

Answer 2

Puck 1 = 12 m/s

Step-by-step explanation:

Conservation of energy

KE_1a + KE_2a = KE_1b + KE_2b

(1/2)(0.1kg)(15m/s)^2 + (1/2)(0.1kg)(12m/s)^2 = (1/2)(0.1kg)(V)^2 + (1/2)(0.1kg)(15m/s)^2

V = 12m/s