Projectile Motion: Motion in Two Dimensions
Simultaneous Fall
PIRA Class: 1D60.20

Purpose
To demonstrate the independence of horizontal velocity and vertical acceleration

Description
Two balls, simultaneously dropped (one projected horizontally), hit the floor at the same time.
1. Mount apparatus on a ring stand such that it extends out over the edge of the counter
2. Cock apparatus's "gun" and load up small white balls
3. Give release arm a sharp knock with a rigid stick
NOTE: Demo is not very effective when used over a carpeted floor (rm 104)
- Have students listen as well as watch for which ball hits the ground first.

PEDAGOGY: Ask students: "If you fired one bullet straight out (horizontally) from a gun, and simultaneously dropped a second bullet from the same height, which of the two bullets would hit the ground first?"

Equipment
Simultaneous fall apparatus w/ accompanying balls
Support Equipment
Rod & Clamps, rigid stick