Torsion pendulum is made from a disk of mass m = 6.3 kg and radius r = 0.75 m. a force of f = 41.7 n exerted on the edge of the disk rotates the disk 1/4 of a revolution from equilibrium. 1) what is the torsion constant of this pendulum?

Given:

m = 6.3 kg mass of disk to be torqued

R = 0.75 m radius of disk

F = 41.7N force applied at edge of disk that rotates it 1/4 turn

θ = - 2π / 4 = - π/2

The torsion constant of this pendulum

= 41.7 * 0.75 / (0.5 * pi)

= 31.275 / 1.5708

= 19.91 Nm / rad would be the answer