PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
Three identical ice-hockey pucks A, B, and C slide without friction across a horizontal sheet of ice.
• Puck A has mass m and speed 2v.
• Puck B has mass 3m and speed v.
• Puck C has mass 2m and speed 2v/3.
Assume all motion is measured relative to the Earth.
(a) Rank the pucks’ translational kinetic energies from greatest to least without performing explicit numerical calculations.
(b) Describe, in words, the reasoning you used to establish the ranking in part (a).
(c) If the kinetic energy of puck A is 15J, calculate the kinetic energies of pucks B and C, showing your work and including units.