Thursday, February 3, 2011
Building the Cannon
After coming up with a design for our cannon we had to actually build it. Our materials consisted of a protractor, 18 inches of tape, 2 tennis ball cans with lids. (If the pictures don't come up try clicking on them, I will try to get it so the other ones work)
Our Design:
Step One: Remove the plastic around the tennis ball cans and cut the metal piece at the tip of tube off
Before:
After:
Step Two: Cut a small sliver out of the tube that was the base and placed the firing tube in the sliver.
Step Three: Adjust the angle as desired using a protractor to measure the angle
Step Four: Place the tubes at a cross keeping the angle measured in step four.
Step Five: Tape the tennis ball tubes together at the desired angle. (I think that we might have moved the tubes a bit while we were taping them leading to higher angle it was more like a 48 degree angle instead of a 43 degree angle.)
Designing the Cannon
When designing our cannon, we had to think about several things. One of our main concerns centered on how we would achieve our desired angle, but other problems such as stability, the ability to stand up on its own, and overall strength of design were important. After looking at several different designs, we decided that we would use the two tennis-can tubes to do a cross with one tube being the base, and the other being the barrel that would fire the ball.
We chose this design because this would have a stable base, the firing tube would be long enough to have good accuracy, and the angle would be easy to adjust. The gas law that our project involves is Gay-Lussac's Law. This supports our project because Gay-Lussac's law states that pressure and temperature are directly proportional if the volume remains constant. When we ignite the ethanol, this will cause a combustion reaction, which will result in an extreme release of heat. This, in turn, increases the pressure, and the pressure will reach a point where it exceeds how much is needed to blow the nerf ball out of the tube. Because the ethanol has a very low vapor pressure, it will most likely saturate the air in the chamber, allowing for rapid ignition, and the nerf ball will launch almost instantly after the ignition. We are a using 99% mixture of ethanol, and the molecular formula for ethanol is C2H5OH. When combusted with oxygen you get C2H5OH + O2 which goes to C2H5OH + O2,à CO2+H2O, then you balance the equation you get C2H5OH + 3O2,à 2CO2+3H2O.
We chose this design because this would have a stable base, the firing tube would be long enough to have good accuracy, and the angle would be easy to adjust. The gas law that our project involves is Gay-Lussac's Law. This supports our project because Gay-Lussac's law states that pressure and temperature are directly proportional if the volume remains constant. When we ignite the ethanol, this will cause a combustion reaction, which will result in an extreme release of heat. This, in turn, increases the pressure, and the pressure will reach a point where it exceeds how much is needed to blow the nerf ball out of the tube. Because the ethanol has a very low vapor pressure, it will most likely saturate the air in the chamber, allowing for rapid ignition, and the nerf ball will launch almost instantly after the ignition. We are a using 99% mixture of ethanol, and the molecular formula for ethanol is C2H5OH. When combusted with oxygen you get C2H5OH + O2 which goes to C2H5OH + O2,à CO2+H2O, then you balance the equation you get C2H5OH + 3O2,à 2CO2+3H2O.
A preliminary idea we had before we decided on the one below (if unable to see images click them)
This was the design we ended up choosing for our final cannon (if unable to see images, click them)
We wanted to find the angle that would launch the ball the farthest, so we used the formula h = -16t2+v0t+h0. To find v0, you need to use the formula (speed (ft/sec))cos(launch angle). We had to guess what the speed in feet per second would be, but we should still find the best angle because if the speed differs it will affect the distance, but the angle should still be the best. This formula finds how high the ball will be fired, and the height directly affects the distance. When we put this formula in a calculator, we found out that a 43 degree angle would give us the highest launch. We decided to double check this so we found a website that would do the math for us. When we plugged in the formula we got a 45 degree angle would give us the best launch. We decided to go with the 43 degree angle because the extra forward force would help compensate for wind.
Here is a math problem that is similar to the problem we had to solve:
A cannonball is shot upward from the upper deck of a fort with an initial velocity of 192 feet per second. The deck is 32 feet above the ground.]
1. How high does the cannonball go? __________ (Remember you are looking for specific part of the vertex.) The cannonball goes 608 feet high.
2. How long is the cannonball in the air? ___________ (Remember you can use the quadratic formula.) The cannon ball is in the air for 12.16 seconds
1. How high does the cannonball go? __________ (Remember you are looking for specific part of the vertex.) The cannonball goes 608 feet high.
2. How long is the cannonball in the air? ___________ (Remember you can use the quadratic formula.) The cannon ball is in the air for 12.16 seconds
To solve this problem you have to use the formula h = -16t2+v0t+h0. v0 is the initial velocity, so that is 192feet/second. h0 is the initial height. which is 32 feet, and t is time. When you plug in the formula you have height=-16t^2+192t+32. You can now put this into a calculator if you substitute t for x. When you put the problem into a calculator you will get a parabola. After getting the parabola in a calculator you solve for the vertex, and the x-intercepts. The vertex is 608 feet high at about 6 seconds, and the realistic x intercept is about 12 seconds. This problem is very similar to the problem that we had to solve for ,except we involved launch angle in ours.
The Ethics of Weapons Development
According to Princeton, ethics is the philosophical study of moral values and rules. The question concerning weapons development asks: "Is it moral for societies to develop weapons of mass destruction (WMD) for any reason?". This cannot be answered easily because there is no exact "right answer". I do believe that if one person has a WMD, then everyone else deserves one WMD, which would provide everyone with the same level of power. Then you couldn't threaten the other people because they could retaliate. In the Cold War, this question became important because everyone was developing WMD's and tensions were high between the U.S and the Soviet Union.
During the Cold War, a principle called deterrence was called into play. Deterrence means keeping the power to prevent an enemy attack, because both sides fear retaliation. Without this principle, a nuclear war between the U.S. and the Soviet Union probably would have erupted. This is why I think that weapons development is important because fear is a great way to prevent attacks. If no one feared nuclear retaliation from the U.S., then they could attack the U.S., which would have no way to defend themselves. Even though there are thousands of WMD's in the world, only two have ever been fired. The two WMD's that were fired were fired were used in order to save lives.
The Japanese were committed to fighting the war until everyone was dead, and it didn't matter which side. So, President Harry S. Truman authorized the dropping of atomic bombs on the Japanese cities of Hiroshima and Nagasaki. The dropping of these bombs convinced the Japanese to surrender, which may have saved lives in the long run, even if it killed people in the short run. However, the unexpected results of the dropping of the bombs came later, with the long terms effects. Tens of thousands of people died from radiation after the initial blast, and tens of thousands passed away later or suffered from from birth defects and disease.
The Japanese were committed to fighting the war until everyone was dead, and it didn't matter which side. So, President Harry S. Truman authorized the dropping of atomic bombs on the Japanese cities of Hiroshima and Nagasaki. The dropping of these bombs convinced the Japanese to surrender, which may have saved lives in the long run, even if it killed people in the short run. However, the unexpected results of the dropping of the bombs came later, with the long terms effects. Tens of thousands of people died from radiation after the initial blast, and tens of thousands passed away later or suffered from from birth defects and disease.
In my opnion, even just maintaining the appearance of being able to prevent anything is key. For example, if the Secret Service did not maintain the appearance that they could stop someone from assassinating the president, then many more people would try and one would probably succeed. When people are manufacturing weapons, they have to understand that the device they are making is meant to kill someone, not heal someone. Weapons are a huge industry, with over 1 trillion being spent on them worldwide. Some of these weapons will go to a good cause, like freeing a country or protecting someone, while others will go to someone who will use them to kill innocent people
In the book "A Long Way Gone" by Ishmael Beah, Ishmael encounters some of the weapons that are being used for bad purposes. If guns and explosives had never been introduced to Sierra Leone, some of the horrible things that happened to Ishmael may never have occurred. He saw babies who had been shot in the back, families killed, and their huts burned. Guns have made killing so easy because all that is required to take a life is to point and pull the trigger. There are machine guns that fire over 50 rounds per second and can cut down a thick tree with ease. Because of this, one person can do the work of an army if he is well equipped. It is easy for one soldier to gun down 10 people at once because of how we have evolved in terms of weapons, but earlier in history killing ten people at once would have been deemed near impossible.
Another issue that we face the way revolutions in weapon design have permitted the act of taking a life to become 'impersonal'. Now, you do not have to see the face of the person you kill and you do not have to see their pain. Because of this, killing is much easier mentally. When you see the face of the person that you killed, it makes a huge difference. For example, Ishmael often had to see the face of the person he killed. which made his experience ten times worse because he could not block out the face from his mind. It stayed with him forever. Guns tore Ishmael's family apart, and he was forced to rely on them to survive. Nno person should be forced to use a gun and kill a person just to survive, especially a teenager. You should never have to choose between your life and someone else's, but Ishmael was forced to make this choice and he chose to live, a choice that most people would choose if given the option. This further exemplifies the issues that weapons cause, especially when put into bad hands.
Social Impacts
Cannons have been used for centuries to help liberate countries from dictators, or to help enslave countries: it all depends on who is using it. In the Revolutionary War, cannons were a crucial part in freeing the colonies. In World War I, the Germans used their super-cannons, such as the Paris Gun, to inspire fear in their enemies. Even though the Paris Gun was not effective at destroying cities or killing people, it destroyed the enemy’s morale, and, without morale, armies cannot function. This played a key part in the German's strategy. A quote from Lieutenant General Leman, who commanded the Belgian forces at Liege, shows how powerful and effective at destroying morale the Big Bertha was:
"We could hear the shells coming. We heard a rushing of air which increased in intensity until it became a furious hurricane roar and ended in a dreadful crash of thunder; fountains of earth and smoke were thrown into the air, and the whole earth shook."
As illustrated in this quote, Big Bertha not only destroyed forts, but also destroyed morale. Below is an image of the destruction from the Paris Gun
Furthermore, in the Revolutionary War, the American colonists trained with artillery daily, and it played a crucial part in the Battle of Yorktown, where the colonists had more artillery than the British, which they used it to bombard them 24 hours a day. Then, when the British were weakened, the colonists were able to overrun them. Meanwhile, at sea, the French were using cannons on board their ships to destroy the British fleet that had come to help Lord Cornwallis.
"We could hear the shells coming. We heard a rushing of air which increased in intensity until it became a furious hurricane roar and ended in a dreadful crash of thunder; fountains of earth and smoke were thrown into the air, and the whole earth shook."
As illustrated in this quote, Big Bertha not only destroyed forts, but also destroyed morale. Below is an image of the destruction from the Paris Gun
Economic Impacts
Throughout history, people have spent tons of money on weapons development. The Ottoman Empire poured money into having the largest and most destructive cannons, while the U.S. government has a military budget over 600 billion dollars. In World War I and II, the Germans spent tons of time and money developing super weapons like the Paris Gun and Big Bertha. Part of the reason that the Germans were partly successful in the World Wars was because of their advanced technology. Weapons have continued to evolve to the point where we can kill hundreds of thousands of people by pressing one button, and there is not really a need to see weapons evolved further. The technology used in cannons has also been changed and modified over time, in the 1800's "rifling" became common on cannons. In modern times, cannons are made to fire at a higher trajectory angle than previous cannons, and they have also been adapted to be used on boats.
When gunpowder and cannons were invented, they changed the way the world looked at warfare. Now, forts weren't effective against the siege weapons and they needed to adapt. Different types of forts were also designed to be effective against new siege artillery. Without the advancement in weapons technology, the world would be a completely different place, possibly for the better, or for the worse. Weapons can be used for good things, such as to hunt, or liberate a country. Weapons can also be used for bad things, like enslaving people, or killing innocent people. Either way, they play a crucial role in warfare that we must consider.
When gunpowder and cannons were invented, they changed the way the world looked at warfare. Now, forts weren't effective against the siege weapons and they needed to adapt. Different types of forts were also designed to be effective against new siege artillery. Without the advancement in weapons technology, the world would be a completely different place, possibly for the better, or for the worse. Weapons can be used for good things, such as to hunt, or liberate a country. Weapons can also be used for bad things, like enslaving people, or killing innocent people. Either way, they play a crucial role in warfare that we must consider.
The Paris Gun (1900's-present)
The Paris gun was used in World War I by the Germans to bombard Paris. This gun was one of the largest guns at the time, as it was capable of firing a 260 pound shell with 15 pounds of explosives in it over 80 miles. This "super cannon" was a rail mounted gun, and was about 111 feet long. When the charge was fired, it would reach an altitude of approximately 24 miles before heading back toward earth.
In World War I, March through August 1918, the Germans fired about 351 shells at Paris. The charges killed 256 people and injured 620. The Paris Gun was ineffective, howeverl because its accuracy was only good enough to hit city sized targets, the payload was small compared to other cannons, and the barrel needed replacement after only 65 shots. Still, this enormous gun was highly effective at wearing away at the Parisian's morale.
Below is an image of the Paris Gun and some of its ammunition.
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