UIUC Physics Lecture Demo: Leaky Cup Drop

UIUC Physics
Lecture Demonstration
Database

Demo # 787

Leaky Cup Drop

ID # 787

Description:

A sturdy, large plastic cup has two holes in its side near its base. Holding your fingers over the holes, fill the cup with water. Show that the water can leave the cup by removing your fingers from the holes one at a time, allowing the water to fall into a bucket. Then drop the cup. The water will not spout out of the cup while the cup is in freefall, because the water and the cup will accelerate at the same rate.

Picture of Leaky Cup Drop

Physics Concept:

Mechanics
Gravitational Force
Measuring g

The demonstration takes about 1 minute to perform.