by: Tami O’Connor
One of the things I enjoy most about my job at Educational Innovations is conducting teacher workshops. It’s not quite the same as being in the classroom in front of twenty-plus students, but it’s fun nonetheless. My favorite presentation is titled, 3-2-1 Blastoff! In it, we deal with energy, forces, and motion. I use the Mighty Missile Launcher to demonstrate these topics.
It is exactly that… a missile launcher. The good news is this missile launcher can be used safely in a classroom with children from kindergarten to High School. Participants need safety glasses or goggles.
The launcher is primarily constructed of a film canister, a straw, and a balloon. The balloon has a sponge-like material inside that functions to re-inflate the balloon quickly. The balloon is attached to the film canister so little air is able to escape. The film canister pivots, allowing you to aim it at differing angles. The four missiles are simply straws, sealed on one end, with foam fins that stabilize them as they fly through the air.
I first demonstrate how the missile is launched. The missile is loaded onto the launcher by sliding it onto the straw that is slightly less narrow than the missile. Since the balloon is connected to the film canister, air can flow easily between the two. Depressing the balloon forces air into the film canister and out through the attached straw. When a missile is loaded onto the straw, the forced air propels it into the air. The harder and more quickly the balloon is squeezed, the faster the air flows into the missile.
Next, I make groups of three or four individuals, and I challenge my teachers to consistently land three out of four missiles inside a target area 1 meter away. Seems like a cinch, right? Not so fast… As with every good science activity, there are several variables that must be controlled. The first is the force at which the missile is launched. The harder and faster the balloon is squeezed, the faster the air is compressed and the farther the missile travels. The second is the angle at which the film canister points. The greater the angle, the higher and shorter (in horizontal distance) the missile travels.