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MrMuffinMan

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Blog Entries posted by MrMuffinMan

  1. MrMuffinMan
    The most important technology that came out of WWII was the nuclear bomb. But the second most important technology and probably the most used today is Radar. Every airport in the US uses Radar to track flights. But the physics behind this technology is very simple. It's the Doppler effect. A Radar system has two parts a transmitter and a receiver. The transmitter sends out a burst of radio waves. These waves go until it hits an object, say a plane and bounce back with a different frequency because due to the Doppler effect a plane moving would cause the waves to bounce back faster or slower depending on the direction of the plane in regards to the transmitter. Then the receiver detects the frequency of the returning waves. Using the equation f'=fo(c+vplane)/c where c is the speed of the waves in air, the Radar computer can determine the speed of the plane. Also the computer can find the location of the plane by using the difference in time from when the waves were sent to when the waves were detected by using D=2Ct since the time is for the waves to get there and back.

  2. MrMuffinMan

    One way only

    By MrMuffinMan,

    Every Police/Law enforcement show has an interrogation where the criminal sweats it out while the detectives stand behind a one way mirror. How do this mirrors work? It's all about the light. Think of you're favorite interrogation room with a one way mirror in it. It's almost always bright in there while the room on the other side is kept dark. you might of thought like I did that it was to blind the suspects but in reality it's how the mirror works. A one way mirror is basically just half a mirror. The glass is treated with a special substance so that instead of every molecule in the glass being reflective which would make it a no way mirror, the reflective molecules are spread out so that only about half the molecules are reflective. Now when the police make the interrogation room really bright, half the light bounces back and there's enough of it to create a reflection. The rest of the light passes though the mirror so that eyes in the other room can take in the light and pass the image to our brain. On the flip side since the other room is so dark, the light from the interrogation room drowns the other rooms light, like a loud noise drowning out a quiet noise, and nether side see the image of the other room in the glass.

  3. MrMuffinMan
    In today's world we've almost all been on a plane at least once in our lives but it was just over a hundred years that the Wright brothers flew for the first time. The physics behind flight is not very complex at all but most people don't think about what's keeping them from dropping 30,000 feet in a 490 ton airplane. In the follow picture we see the all the forces acting on the plane and we all know that for the plane not to fall from the sky the net force in the up direction has to equal 0 so the lift has to be greater than the weight of the plane. But what causes lift? Fluid Dynamics. Even though air isn't a liquid it's still a classified as a fluid and follow the same rules. According to Bernoulli's Principle, faster flowing fluids exert less force than slower moving fluids. So when the air flows over the wing, it has to go further because of the shape of the wing so it goes faster and exerts less force than the air flowing underneath the wing. This creates a force up lift which is how a plane stays in the air.

  4. MrMuffinMan
    Were as the idea for planes and the physics behind them make sense, the helicopter is completely different. In order to create the same lift as a plane does by getting air pass over the wings very fast, a helicopter has to lift by spinning it's rotor blades very fast. the same principle of fluid dynamics is responsible for the lift force on a helicopter. The blades on a helicopter are shaped almost the exact same as plane wing so that when they are spun they create a upward force on the helicopter. All the blades together spinning create a small low pressure system above the blades and the air below pushes up. However since the helicopter is in the air, they is no force to stop the cabin of the helicopter from being spun the other way which is why almost all helicopters have the tail rotor which uses the same physics to create a force that keeps the fuselage from spinning. Using physics we have been able to conquer the sky.

  5. MrMuffinMan

    How Bullets fly

    By MrMuffinMan,

    Skipping the intro, bullets gain all of their kinetic energy from expanding gas. When the trigger is pulled, the firing pin in the gun comes forward and ignites the gun powder in the shell. The chemical energy stored in the powder is then convert into heat which cause the temperature of the the air between the bullet and the shell to rise rapidly. Remembering the equation from last year PV/T=PV/T this shows that when the temperature increases ether the pressure or volume has to increase also. In this case, the first thing to increase is the Pressure and this increase pressure creates a force on the bullet that sends in flying out of the barrel. All of this happens in a fraction of a second.
  6. MrMuffinMan

    10

    By MrMuffinMan,

    Time to finish this. And This is just going to be all about how i feel the class is going so far. Right now I enjoy this class because it's not extremely hard. Yes the tests are hard but we're not learning anything new were just using derivatives and integrals on equations we used last year. I think the reason we think the tests are so hard is because we're not always taught everything that's going to be on the test and Mr. Fullerton leaves some stuff for us to figure out; which wouldn't be to bad except we don't always have enough time during the test to work through the problem and discover the trick. Like i remember on one test, we had to figure out an equation for the horizontal distance a projectile was going to travel given only the vo and the angle. When i got to this question i just when oh **** and moved on which is what most people i assume did. But going back and looking at it later i realized that it wasn't too bad because we could solve for time in the air and multiply it by the velocity in the x direction. But also there was a trick that you had to remember that 2sin(x)cos(x)=sin(2x) which i feel like would of thrown a lot of people off if they got to that point and didn't remember. I hope that as the year goes on I will be able to see things like that faster and be able to work my way through problems the likes of which i have never seen before.
  7. MrMuffinMan
    http://crazyarcade.wikispaces.com/file/view/dagobah_happy_wheels_DEMO.swf/182259727/dagobah_happy_wheels_DEMO.swf

    Before reading this you should play this game and warning it is pretty gruesome.


    This game has pretty good physics mostly although some parts of the game defy real life. For example the projectile motion is great because when you go off a jump or are sent flying by a land mine your body as well as the part of body that were probably blown off all have a parabolic path. Even the blood spurting out of your body follows projectile motion. You can also see that all objec
  8. MrMuffinMan

    E=mc2?

    By MrMuffinMan,

    We all remember E=mc2which we have heard about ever since we started science and learned about last year. But we didn't learn that that's only part of the equation. The whole equation is E2=(mc2)2+(pc)2 where P is momentum. If an object is stationary, it has no momentum and therefore we're back to E=mc2. Also if an object has no mass(aka light) then E=pc. So the smaller something is mass-wise, then the more like light it acts. Like an electron for example has such a tiny mass it almost acts like light. Velocity is the equal to c*pc/E. You can see that if an object is stationary, then E=mc2 and P=0 so v=c*0*c/mc2 and v=0. This shows that an object with mass can never get to the speed of light because as long as it has mass, the momentum can never be equal to E but it can get very close so pc/E will get close to 1 but never will reach 1 so v can never equal c, it can only get really really close.


  9. MrMuffinMan
    Released in 1984 Tetris has been confounding physicists as to how the blocks move in the way they do. Now almost 30 years later, the secrets of tetris have final revealed. The blocks are moved using a combination of magnetism and electricity to move the block sideways and down. Unseen to the player each block has a slight positive charge and at the bottom of the screen there is eletric plate that is negatively charged. This causes the block to accelerate downward but it is only on for a few milliseconds before it's turned off in order to keep the block at a constant velocity. As the game goes on, the plate is left charged for longer which means the block reaches a faster speed. When the player presses the down button, the plate becomes negative charged again, causing the block to accelerate again. In order to move the block left and right, when the player press the left or right buttons the game creates a magnetic field. Since the blocks have a velocity downward, the magnetic field exerts a force on the block to the left or right. For example when the play press the right button, the game creates a magnetic field into the screen and by the right hand rule, the block feels a force to the right. And when the player presses left, it creates a magnetic field out of the screen which sends the block to the left. In order to turn a block, the game has to create two magnetic fields in opposite directions(one in, one out) that split the block in half(top and bottom). This creates a torque on the block that causes it rotate. Finally once a row has been filled, it completes a circuit that now has a current running though it. Behind the screen, there is a wire carrying current in the same direction and since wires carrying current in the same direction attract, the row is sucked behind the screen leaving space for the remaining blocks to slide down. Tetris may seem like it defies most laws of physics but we can see that it has to follow the same rules as all of us.
  10. MrMuffinMan

    Physics of Tennis

    By MrMuffinMan,

    The sport of tennis is the oldest and most love sport in the world. People have been playing tennis ever since the Acient Greeks took a stone and started hitting it back and forth over a fallen tree with branchs. Granted back then the sport was much more dangerous; many an acient greek lost an eye or a limb due to getting hit with the sharp rock that they played with, but even today the physics that govern the game today with the tennis balls with fuzz that sticks to your socks remain the same. Tennis is all about redirection of energy. A ball bouncing off the ground is effected by an impulse that changes the direction of it''s velocity. Current tennis balls are usually so bouncy that the collide elastically with the ground which means there's no loss in energy or speed. Then when the player hits the ball, the player usually swings the racket(or tree branch) which absorbs some the the energy so when the player hits teh ball some of the energy is lost but the ball gains more energy coming off the racket because it gains energy from the racket that has it's own energy that is transfered to the ball. Top spin on the ball causes it to go down because relative to the ground, the top of the ball is moving faster than the bottom so, air is flowing over the top faster, which causes the air to exert a force on the ball downward.
  11. MrMuffinMan
    This again come from MindCipher.com.

    A person is holding on to a helium balloon in an elevator. The elevator cable snaps, and at the exact same moment, the person lets go of the helium balloon. In the perspective of the person in the elevator, what happens to the balloon the moment the cable snaps?
  12. MrMuffinMan
    Red Remover is a puzzle game which relies heavy on the laws of physics and breaks almost all of them at the same time. Red Remover is a game where you have to remove all the red blocks by click on certain blocks and making them disappear. This is the and most fundamental law of physics that this game breaks because matter and energy can never be destroyed and even if by clicking on the block caused them to turn into energy, there would be so much energy that it would blow all the near by blocks off the screen. In order to get the red blocks off the screen you have to remove block that are just floating in mid air that feel no effects by gravity. Once these blocks are gone, the blocks that have faces will feel the force of gravity but instead of accelerating the move at a constant speed. Also there are four planes of gravity, one going in each direction, and blocks are only affected by one if any of the forces of gravity. This is wrong because gravity doesn't choose what objects it wants to affect, it has to affect all objects. However this game is very good at the physics of collisions between blocks. When two blocks collide, the will usually continue to move, but the direction they move will change according to where the other block was heading. Even though this game breaks many of the fundamental laws of physics, it is a very good demonstration of have collision can affect objects.http://www.physicsgames.net/game/Red_Remover_Player_Pack_2.html
  13. MrMuffinMan
    March has always been the worst month of the school year and this was no exception. A combination of harder classes, more homework, sports and the increasing effectiveness of seniorities turned the last week of the 3rd quarter into a cram session of trying to get everything done. Seeing how I am doing these blogs, it's clear how far behind I was and still am. This has been a rude awakening as to how much stress procrastination causes and I hope that I will be able to put off seniorities until after AP
  14. MrMuffinMan
    A bottle rocket works because of Newton's third law of motion. As more air is pumped into the "tank" the pressure increases so that when the restraint holding the rocket in place is removed, the pressurized air forces the water out of the bottle. Newton's third law states that for every action there is an equal and opposite reaction. This means that water exerts an upward force on the bottle itself. This is what sends it into the air. A nose cone works by cutting through the air instead of the blunt bottom of the bottle forcing itself through the air which would increase drag. Fins help by stabilize the flight via air flowing over them helping keep them and the rocket in line. Finally the parachute works by increasing the drag force caused by air so much that it slows the rocket down to a speed safe for landing
  15. MrMuffinMan
    Real rockets work just the same as the model bottle rockets that we made for arts fest. Rocket engines instead of using water expel gases and the pressure that is used to expel these gases come from the burning of fuel.When the fuel is burn, the energy released increases the temperature of the gases that created when this fuel is spent. These super heated gases want to expand which causes the pressure to increase. As the pressure increases, the gases are pushed out the back end of the engine which because of Newton's third law of motion also push the rocket engine and everything attached to it in the opposite direction.
  16. MrMuffinMan

    Solar Sails

    By MrMuffinMan,

    Currently the only way for us to get around in space is to use rocket fuel and chemical reactions to push the rocket around. This is very expensive and current rockets are 95% fuel by weight. However NASA is developing an alternative that uses the the sun to push the rocket around. These solar sails are made with large ultra-thin mirrors that use the light of the sun to push the sail around. These sails have to be reflective because when the light hits the said it has to be reflected. This they key because thanks to DeBroglie, we know that light has momentum and as the light changes direction it exerts an impulse on the said which accelerates the sail. Granted this force is tiny compared to rocket engines, but in space the the sail will accelerate as long as it sees sunlight which means it can go much farther without fuel on board.
  17. MrMuffinMan
    The greatly feared captain of the pirates "Schalkimnack" was not only famous for his cruelty but also for baffling his prisoners with difficult brain twisters. This is one of his favourite riddles:
    Schalkimnack took a gold coin an throw it overboard into the sea. He asked:
    "Did the sea level ...
    a) rise,
    sink or
    c) stay like before?"

    If one of the prisoners could solve the riddle, he was set free, but in case of giving the wrong answer, he was thrown to the sharks. Legend relates that until now, nobody could manage to solve the riddle.
    Now you've got caught by Schalkimnack!

    Can you solve the riddle?



    website for this riddle
    http://physik.ph-gmuend.de/brain-teasers/

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