Question

A meterstick of negligible mass is placed on a fulcrum at the 0.4 m mark, with a 1 kg mass hung at the zero mark and a 0.5 kg mass hung at the 1.0 m mark. The meterstick is held horizontal and released. Immediately after release, the magnitude of the net torque on the meterstick about the fulcrum is most nearly:________

a. 1 Nm
b. 2 Nm.
c. 2.5 Nm.
d. 7 Nm
e. 7.5 Nm

Answer 1

The net torque is 0.98 Nm.

Step-by-step explanation:

The torque is given by

Torque = force x perpendicular distance

The clock wise torque is taken as negative while the counter clock wise torque is taken as positive.

Take the torques about the fulcrum.

Torque = 1 x 9.8 x 0.4 - 0.5 x 9.8 x 0.6

Torque = 3.92 - 2.94 = 0.98 Nm