PhysicsLAB: Test Scenario: Torque

The following masses are supplied for a group of students to bring a uniform meter stick torque bench into balance: one 50-gram mass, one 20-gram mass and one-10 gram mass. They are also supplied with a new 105-gram meter stick that has its center of mass located at 50.0 cm.

Refer to the following information for the next four questions.

They are told to place the knife-edge (or fulcrum) at the 40 cm mark and to place their one 50-gram mass at the 30-cm mark. The students are then given the direction to add whichever of the remaining masses that are needed to bring the stick back into equilibrium.

(a) What direction torque is supplied by the original 50-gram mass?

ClockwiseCounterclockwise

(b) What direction torque is supplied by the center of mass of the meter stick?

ClockwiseCounterclockwise

(c) Show your solution process (equations and calculations) to determine which mass or masses would be needed and where they should be placed to set the meter stick back in rotational equilibrium.

(d) How much supporting force was provided by the fulcrum?