Three cyclists A, B and C ride on three concentric circular tracks in the same…
PHYSICS · Multi-part · A Level · Physics · Further mechanics and thermal physics · Further mechanics and thermal physics
Problem
Three cyclists A, B and C ride on three concentric circular tracks in the same horizontal plane. The radii of their paths are 6m, 12m and 18m respectively. Their linear speeds are 5ms−1, 7ms−1 and 9ms−1 respectively.
(i) Without performing detailed numerical calculations, arrange the cyclists in ascending order of the magnitude of their centripetal acceleration.
(ii) Justify the order obtained in part (i) by using the proportional relationship between centripetal acceleration, linear speed and radius. Show the algebraic steps that lead to your conclusion.
(iii) If the speed of cyclist B is doubled while the radii remain unchanged, predict qualitatively (no calculation needed) whether B now moves to first, second or third place in the order obtained in part (i). Give reasons for your answer.