A mass–spring system hangs vertically and oscillates about its equilibrium position
PHYSICS · Subjective · A Level · Physics · Further mechanics and thermal physics · Further mechanics and thermal physics
Problem
A mass–spring system hangs vertically and oscillates about its equilibrium position. Displacement y is measured upward from equilibrium (y = 0 is equilibrium, upward is positive). Write an expression for the net force F_net on the mass in terms of y, and in one sentence explain why a negative displacement produces a positive net force in your expression.