PURPOSE: To demonstrate that the path a of projectile has a maximum range at a 45 degree angle of launch.
DESCRIPTION: A water stream is made to flow from the nozzle of a small eyeglass dropper that is held in place by a U shaped arm. The stream of water is shadow projected using a bright point source of light from a carbon arc lamp. The angle of the projected stream of water can be adjusted by rotating the U shaped holder. A can of water acts as a reservoir and provides nearly constant water pressure. Note that the water pressure does change as the level of the reservior in the can is lowered.
EQUIPMENT: Hose stored in the hose rack near the sink. Eyedropper and water tray are stored in the drawers beneath he chemical cabinet. The water bucket and adjustable clamp are stored in mechanics. Carbon arc is stored in general use.
SETUP NOTES: Faculty should practice.
It is important to remove the air from the hose to prevent the break up of the water stream. The air must be painstakingly pinched out from the hose by hand. Als, use a small drop of soap in the water to lower the surface tension.
Video of Demonstration for Quicktime
Video of Demonstration for Windows Media Player