Static Torque: Statics of Rigid Bodies
PASCO Blackboard Mechanics: Arm
PIRA Class: 1J40.75

Purpose
To observe & measure balanced torque on an object.

Description
Two forces are applied to a lever arm (model of the human arm) such that the lever arm remains stationary (i.e., arm does not rotate. Set up shown a spring scale biceps muscle pulling up on the arm and a weight in the "hand" pulling down on the arm).
1. Measure & note the distance from the pivot point to the spring scale and the spring scale reading.
2. Measure & note the distance from the pivot point to the "hand" and the weight of the masses "in the hand".
3. Verify F x d (spring) = -Weight (Fgravity) x d (hanging mass)

Equipment
PASCO's Blackboard Mechanics: magnetic pivot arm, spring scale, and hanging masses