Reflection

Ours did not shoot or even budge. It just burned the plastic. The reason it didn't work is for two reasons. One is the Gay-lussac's law states that the colder the air the less volume of a gas. So the co2 wouldn't expand as much as expected. Therefore the ball didn't shoot. The reason the plastic burned is because, in our design, the combustion chamber was doubled up and there was one tube of plastic inside another so the plastic wouldn't expand and there would be more pressure on the ball as opposed to more pressure on the plastic going outwards. Therefore, we had to make two holes in the combustion chamber and when we stuck the burning stick inside the combustion chamber to light the ethanol, we put the stick through the first hole but not the second hole where the ethanol is. So it just burned the plastic. And that is why the cannon failed. If we could do this differently we would change the design so the combustion chamber wasn't doubled up.

Design

Today we shot of the cannon. Our design was a combustion chamber and a barrel that was 1.5 times the size of the combustion chamber. There was a plastic separation between the combustion chamber and the barrel. Then you poke holes in the plastic separation and put ethanol on both sides of the separation. This magnifies the blast and sends the ball flying.

M4 Sherman

M4 Sherman

1900's

This tank was used by the USA during WWII. This was basically a well-rounded weapon. It was easy to make, reliable, and fast. It stood well against other tanks. Except for German Tiger Tanks. They were Medium strength but High to US standards. But it isn't the tank, it is the people operating the tank. We were able to out maneuver them and had better flanking tactics. The majority of losses of this tank were land mines. The M4's traction isn't very good on mud or snow, compared to desert or hilly terrain. The armor was 63 mm for the Hull. The M4 got grave nicknames because they were prone to burning when hit by large shells. They were over all, a very good and successful tank.

Howitzers

The Howitzer

1800's

The Howitzer were used by the Confederates during the Civil War. They were short barreled guns which fired explosive shells and had a high trajectory. They are similar to modern day mortars. They are used to shoot projectiles over high walls (i.e. into a fort). It was generally made of bronze. They are similar to cannons but in a box container that keeps them pointed high. So the Projectile goes higher than it does farther. One problem could be accuracy. It is more of a point and shoot cannon.

The Ballista

The Ballista

pre-1800's

The Ballista was first invented by the Romans in 399 B.C. They combined two Greek weapons to make theirs. It works like a extremely big crossbow, and The Ballista is used for siege technology. They way it works is: one person will wind a crank pulling back the string, drawing the crossbow. Then they put the projectile in front of the string. When it is released, it will send the projectile flying through the air. The Romans were also know to be able to pick certain people out using this weapon. Obviously, it is very accurate. "Ballista" means "Throw" and is a Greek word.