Why I built a Trebuchet

When I was in 6th grade we had an assignment to build a catapult to see who could launch a golf ball the farthest. The current school record was 30 feet. Our job was to try and beat the record.
My Dad and I talked about different catapults to build and we decided to build a trebuchet because we thought it would throw a golf ball the farthest.

History of the Trebuchet

The trebuchet was the dominant siege weapon in Europe from 850AD to 1350AD, lasting 100 years after the introduction of gunpowder. In England it was called An Ingenium, and the technicians, which worked on the weapon, were Engineers. Larger versions were able to throw large stones, cows or even shunned negotiators. Rotting flesh was also popular.
The trebuchet operates by harnessing the potential energy of a suspended weight, and demonstrates many physical pricipals. There are multiple variables in the design which can be adjusted to optimize range and throw-weight.
"Hurling" has become a gentleman's sport in Texas, where a active hurling society exists. Work is being completed on "Thor", a Trebuchet with a 100' throwing arm using a 55,000 lb weight. The design should allow the hurling of '57 Buick's. In earlier days some Texas trebuchets have thrown 'astro-aguanauts'. The trebuchet took 15 minutes to reload, thats why the wars took so long.

Construction of our Trebuchet

We should have taken pictures while we were building our Trebuchet, but we forgot to at the time. But it was fun trying to build a trebuchet by our selves by scratch.
Our arm is 47 inches long. The pivot point is 20 inches from the base and we used 25 pounds of lead shot as the counterweight. I think we can put more lead in and get more range. The sling is built out of the leg of my old blue jeans and the cords are about 12 inches long.

Our Results

The first shot out of our Trebuchet wasn't very good. It shot 10 feet backwards. Later after we tuned it we could easily toss a golf ball 90 feet.
When I brought it to school for the demonstration, the first shot went backwards again. Boy was I embarrassed. The second shot was much better. We got 90 feet out of it and shattered the school record. None of the other catapults even came close.

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