Purpose
The steelyard balance has been around since ancient times. It works by employing a counterweight and lever to weigh objects. Leverage is adjusted by sliding the counterweight on a metal arm. The balance may be used to demonstrate the principles of torque and center of mass.
Parts
- The steelyard balance is found fully-assembled on shelf C3.
Setup
The balance has two scales, both calibrated in pounds, that allow the determination of an object’s weight by attaching the object to the hook on the shorter arm, sliding the counterweight until balance is achieved, and noting the position of the counterweight. For lighter objects, one should use the scale containing smaller weight readings (and the scale having larger weight readings for heavier objects). Scales can be switched by flipping the lever arm construction — this allows one to attach heavier objects closer to the axis of rotation and lighter objects further away.