A body of unknown mass is attached to the lower end of a light vertical spring

PHYSICS · Subjective · A Level · Physics · Further mechanics and thermal physics · Further mechanics and thermal physics

Problem

A body of unknown mass mm is attached to the lower end of a light vertical spring. When set into small vertical oscillations the period is measured to be T1=0.40 sT_1 = 0.40\,\text{s}. (i) Deduce, in terms of mm, the spring constant kk of the spring. (ii) Another body of mass 0.50 kg0.50\,\text{kg} is gently placed on the first body so that both masses move together. The new period of small vertical oscillations is found to be T2=1.5 T1T_2 = 1.5\,T_1. Show that the unknown mass is approximately 0.40 kg0.40\,\text{kg}. (iii) Using the value of mm obtained in part (ii), calculate the numerical value of the spring constant and the natural linear frequency of oscillation before the second body was added.

Related theory

Browse the problem library