"Sweet Spot": Meterstick pivot point changes with point struck.

Rigid Body: The Sweet Spot. If the meter stick were a baseball bat,and the P.I. was the ball hitting the Sweet spot, then there would be minimum movement at the batter's wrist to jar the batter's hands and arms... A Meter Stick (or Baseball Bat) is placed on the lecture Table, and a 'cue' stick (another meter stick or pointer) hits the Meter Stick at the Point of Impact (P.I.). At the Sweet Spot, the Meter Stick rotates around one of its ends.