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Click here to download the original worksheet

Click here to download the original worksheet

 

The advantage of fission is that it will result in a lot of heat energy which can be used to generate electricity.  The problem is that once a chain reaction gets going, it can get out of control, and generate a lot of heat very quickly.  This is basically an atomic bomb, or as Mr. Burns calls it 'an unrequested fission surplus.'  Here comes in the inanimate carbon rod.  In reality it is a control rod, and instead of carbon it is made of boron, silver, indium or cadmium.  The rods can be placed in-between the uranium/plutonium and absorb the extra neutrons, thus slowing down the rate of fission.  Here's another physics textbook diagram that will do a much better job of explaining it than my ramblings:

Deep space homer

I was watching The Simpsons last night and episode 'Deep Space Homer' was on.  I thought, if I could make a review of all the physics for students studying physics to try and link it to topics they have already seen.

The inanimate carbon rod!

A nuclear power station harnesses energy from nuclear fission.  Fission is the process where you fire slow moving neutrons to uranium or plutonium.  The uranium/plutonium atoms 'captures' the neutrons, which makes the atoms unstable.  These atoms split (fission) apart into two smaller atoms, and several neutrons.  A lot of energy is released in the process as well, which is what is used to generate energy.  The extra neutrons that the uranium/plutonium atom shoots out will end up getting captured by other atoms, and the process is repeated.  This is called a chain reaction, and here's a dull physics textbook diagram to explain it.

Left: Control rods placed in-between uranium/plutonium, slowing down the chain reaction. Right: Control rods raised above uranium/plutonium, allowing the rate of fission to increase.

Left: Control rods placed in-between uranium/plutonium, slowing down the chain reaction. Right: Control rods raised above uranium/plutonium, allowing the rate of fission to increase.

Centripetal force

The name of the machine Homer is in is usually something called a 'centrifuge', it's used to give would be astronauts a sample of what the forces of lift off are like.  The force he experiences is centripetal force. 

Again, this is an example of centripetal force.  You can read check out my Thor article for a more in depth explanation.  What we need to know is the formula for centripetal force is:

In this case the Force will equal 85 kilograms, multiplied by 3 m/s squared.  Then all of that divided by 7 metres.

When we plug the numbers into the formula above we get that Barney experiences 110 Newtons of force.  About the same as having 11 litre sized cartons of milk resting on your chest.

Under Pressure

As Scratchy is exposed to the vacuum of space, the gas inside him is at a much higher pressure compared to his surroundings.  This causes him to expand.

In reality, humans have survived accidents while testing flight suits and space suits in vacuum chambers without their eyeballs popping out of their skull.  However the exposure to the low pressure can kill within minutes.  In 1966 Nick Piantanida was in a high altitude balloon trying to break the world record for highest free-fall when the faceplate of his pressure suit ruptured. This resulted in explosive decompression, and a four month coma that sadly resulted in Piantanida's death.

Well that was cheery, wasn't it?  Let's move on.

freedom! Horrible, horrible freedom!

Newton's First Law of motion states that 'An object will move with a constant velocity or remain at rest, as long as there is no external force acting on it.'

This means that as there is nothing pushing against Homer as he moves towards the ant colony there is nothing to slow him down, resulting in painful freedom for antkind.

Another example of this would be sliding a hockey puck on ice.  The puck will continue to move at a constant speed until something hits it.

The pressure is too great

A lot of times people like to say in cases like this that Homer would be 'sucked out' into space.  But technically the correct term is 'blown out'.  As the pressure is much greater inside the shutter than in the vacuum of space, when the hatch is opened, the gas inside the shuttle will blow out until the difference in pressure inside the shuttle and outside are equal.  As Homer wasn't strapped in, he too was also blown out in the process.