An ice-hockey puck of negligible air resistance slides off the flat roof of an arena…
PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
An ice-hockey puck of negligible air resistance slides off the flat roof of an arena at a speed of 6.5ms−1. The roof edge is 20m above the ground at the point of departure. The ground immediately below the edge slopes downward at an angle of 15∘ below the horizontal, forming a straight hillside surface that extends indefinitely.
(a) Derive an expression for the time t it takes the puck to strike the hillside in terms of its initial speed v0, the roof height H, the hillside angle θ, and the free-fall acceleration g.
(b) Using the expression from part (a), calculate the numerical value of the time of flight for the puck.
(c) Determine the horizontal distance from the roof edge to the point of impact on the hillside.
(d) Calculate the component of the puck’s velocity that is perpendicular to the hillside surface at the moment of impact.
(e) Discuss how the time of flight would change, if at all, if the initial speed v0 were doubled while all other conditions remained the same. Provide reasoning to support your answer.