Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

A 0.18 kg hockey puck, initially at rest, is launched with a speed of 15 m/s acr

ID: 1387337 • Letter: A

Question

A 0.18 kg hockey puck, initially at rest, is launched with a speed of 15 m/s across a rectangular ice rink, making elastic collisions at points A and B, as shown below. Assume that the speed of the hockey puck remains constant throughout its motion. a.Calculate the impulse (magnitude and direction) exerted on the hockey puck by the hockey stick during its initial launch (from rest). b.Calculate the impulse (magnitude and direction) exerted on the hockey puck by the wall during its collision at point A. c.Is the magnitude of the impulse exerted on the hockey puck at point B greater than, less than, or equal to the impulse at point A? Justify your answer.

Explanation / Answer

let east be +x axis


a) Impulse = chnage in momentum

= m*(v2-v1)

= 0.18*(15-0)

= 2.7 N.s

direction : 30 degrees with +x axis

b) There is no chnage in momentum in x-direction.

Impulse(in y direction) = m*(v2y - v1y)

= 0.18*(-15*sin(30) - 15*sin(30))

= 2.7 N.s

direction : towards -y axis

c) same

Because change in magnitude of momentum is same in both cases.

at point A momentum chnages in y-direction, but at point B momentum changes in x-direction.