The Gay Lussac's law states that the volume is constant and the pressure of gas is proportional to the temperature in the project.When lighting the ethanol, it increases the temperature in the ethanol and the volume of its gas increases and pushes the ball out.
Chemical Equation for the combustion of Ethanol Oxygen:
C2H5OH+3O2---2CO2+3H2O
Launch Angle/Justification(usingmath reasoning): Our group chose an 45* to angle our cannons because we think that 40* would be too low and anything aimed to higher than 50* would shoot straight up and not get our maximum shooting range.
We choose our design because we believe that is the most efficient design because of its reinforced areas and chambers.
What you would do differently? The thing that I would do diffrently would be not using the very bottom base as a holder at the end of the cannon.I realy do not see the need for that extra part.
Difficulties in construction: In constructing the cannon we had difficulties trying to allow the cannon to stand. Our first try was cutting the lids of tennis ball cans and trying tomake a stand for it but it did not work.
Record the distance your cannon shot the nerf ball.(do in March)
Materials: 2 tennis ball cans with tops,scissors,and an 18 inch piece of tape.
1.Measure the first tennis ball can 4 inches above the bottom of the bottle . Then after the first mark draw a second mark with within 4 inches of the first mark.Cut the first Tennis ball can first and second mark of the cannon.Then we stab a hole on the bottom piece left over near and measure three inches from the bottom to allow the gas to escape.We do this same procedure for the second tennis bottle can we have. Exception:do not put a hole 3 inches above the bottom of the bottle of the second tennis ball can.
2.Then take the Second tennis ball can and cut the bottom of the bottle off where the first mark from the bottom starts and then cut the second mark which is at the top of tennis ball bottle off.The second cannon you should do the same rules.
3. You just have the base of the tennis ball can left over.After you cut the two bottles you should have a top Part, a cut middle part bottle and half of the end of the first bottle on bottom. Put them all together.Remember if you have cut the wire on the second tennis ball bottle do it now we need it later on on you should only have a top plastic par of the bottle with the wire on top of it.
4. Tap these pieces together with duct tape to hold them in place.
5.After taping the pieces together measure 45 degrees from the bottom of the cannon and then once you get a mark of 45* insert the last part of the tennis ball cannon which is the very base of the cannon we cut earlier and insert onto the end of the cannon.
6.Take the piece of silver wire left and insert it onto the the front of the cannon to raise the cannon to shoot a little higher.
Expected Results/Intial Velocity:
Our group found this formula from research:

So We used 12 which was the seconds the cannonball flew in the air. We multiplied 12 times 32ft .We arrived at the answer of 384.Then we plugged in our calculator sin(45). We got the answer of .707sin.Then we multiplied .707 times 2.Which gave us the answer of 1.41.We divided 384 by 1.41 and got the answer of 272 ft per second for velocity.
So with our findings of the intial velocity my trajectory predictions are that higher the cannon goes up in the air,the slower it falls down in the air.
Cannon Construction Plan:
