A curling stone of mass 20 kg slides across level ice at an initial speed of 1.50 m/s
PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A curling stone of mass 20 kg slides across level ice at an initial speed of 1.50 m/s. Two different training strategies are proposed to increase the stone’s linear momentum before delivery in competition:
• Strategy I: Attach a 10 kg mass to the top of the stone while maintaining the original speed.
• Strategy II: Leave the mass unchanged but increase the speed to 3.00 m/s.
Assume the direction of motion remains unchanged and friction is negligible during the brief acceleration phase.
(a) Calculate the initial linear momentum of the stone.
(b) Determine the linear momentum the stone would have after each strategy is implemented.
(c) For each strategy, compute the percent change in momentum relative to the initial value and state which strategy produces the larger percent increase.
(d) For an arbitrary object of mass m moving initially at speed v, an athlete can either increase the mass by a factor k (>1) while keeping speed constant, or increase the speed by the same factor k while keeping mass constant. Derive an algebraic expression that compares the resulting momenta for the two strategies and indicates which strategy is more effective for any chosen k.