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MrMuffinMan

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  1. 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.
  2. MrMuffinMan
    1.) Don't catch senioritis too early
    2.) Don't wait til last minute to do your blogs
    3.) Watch the videos on Aplusphysics.com
    4.) The book is your friend
    5.) Try on the four minute drills
    6.) Look at notes from AP-B
    7.) Find a friend who knows what they're doing
    or
    8.) Teach your friends what to do
    9.) Stay ahead on independent units
    10.) Don't freak out and have fun
  3. MrMuffinMan
    Faraday Cages are used to cancel out electric fields and block most forms of electromagnetic radiation. And people in today's world have used this in some creative ways. Some people put their phones in these cages so that they can't receive any calls or texts. But I was reading and this article said that a shop lifter had be caught with a bag lined with aluminum foil. This created the bag a Faraday cage so that when the person put the item they were stealing in the bag, the bag blocked most of the signal from the tag that make the sensors by the doors of stores go off when someone tries to shoplift. However this person didn't manage to get a complete cage and the alarms went off. This is just a very different application of physics than we learn in class but it's still cool
  4. 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?
  5. MrMuffinMan

    Atomic Clocks

    By MrMuffinMan,

    Atomic clocks are the most accurate clocks we have and without them, everyone's time could be a little off which would mean GPS navigation would be impossible and other things that rely on exact timing, like space flight wouldn't work. Most atomic clocks are made of cesium and measure the frequency of oscillation. Cesium atoms are given energy in the form of heat and this causes the atoms to change energy states and start oscillating at their principal resonance which is a know value. Measuring the resonance of the Cesium and dividing it by the principal resonance the clock can measure 1 second almost exactly
  6. MrMuffinMan

    Big Bang Board

    By MrMuffinMan,

    So I was watching an episode of the Big Bang theory and in the background of the scene i was watching was a physics equation. It said F=dP/dt which is an equation that i have never seen to before and I wondered if it was true. On the board it went on to expand the equation to F=d(mv)/dt=m*dV/dt and since dV/dt=a F=ma which is the Newton's law that we all love and know. I just thought that this was an interesting and new way to look at a very well know equation

  7. MrMuffinMan
    We have been told that nothing can go faster than the speed of light but what happens if we took a very long arm and rotated it around an axis. When a wheel is turning, the edges are turning faster than the middle in order to keep up. Lets say we took a laser pointer and pointed at the moon which is 384,400 km away, and flicked our wrist and a radian per second then the end of the laser pointer would be traveling 384,400,000 which is faster than the speed of light. So would the end of the laser be moving at faster than the speed of light?

  8. MrMuffinMan

    Catapults

    By MrMuffinMan,

    There were many different types of catapults but every single one relied on the same principles. They all took potential energy, and transferred it into kinetic energy that sent the balls flying across the field or at least tried. There were different ways of storing the potential energy; spring potential energy or gravitational potential energy. Both proved to be very effective. However what really separated the best from the rest was the use of a slingshot. A slingshot increases the effectiveness of the catapult because slingshots allow the ball to swing around the end of the arm which increases the speed of the ball. Also the slingshot allows the arm of the catapult to get moving before the ball starts moving which then causes the ball to accelerate faster to catch up with the arm which made the ball come out faster and therefore go further.
  9. 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.


  10. 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
  11. MrMuffinMan
    This year has gone fast. It seemed like only yesterday that summer ended and we started our senior year. This senior year has been the best year by far and now that it's almost over it's hard to realize that we're almost done. Physics this year has been a great experience. The independent units were probably my favorite units because I could do everything at my pace which was great until my pace was too slow and I found myself cramming to get everything done the last week. They have been an eye opening experience to how college is going to work because I'll have to set my own pace all the time. And even when we didn't have independent units, Mr. Fullerton taught us, but it was our responsibility to look up in book the stuff we didn't understand the first time or ask him which happened a lot more times this year than any other. Mr Fullerton might of taught us Physics for the exam, but he also taught us what we are going to have to do for college and that is probably the lesson we all will remember in the next few years.
  12. 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.

  13. MrMuffinMan

    Fire Physics

    By MrMuffinMan,

    What is fire? Fire is hot but where does it come from? Fire is the result of extreme heat, usually when organic chemicals combusted with oxygen(thank you chemistry) but where does the light come from? The light results from electrons absorbing the heat energy and jumping up energy levels like we learned last year and the light is produced when the electrons fall back down to their ground state. However fire can look different. The fire from Bunsen burners in chem or propane fires look a lot different that wood fires. The propane fires burn cleanly and they give off blue light. However wood fires don't burn cleanly and there is some blue light but soot and other particles that are burning red hot give off the red glow.

  14. 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.

  15. MrMuffinMan

    First post

    By MrMuffinMan,

    I'm going to start off with why I'm taking AP-C physics because I think that's the best place to start. But anyways I'm taking AP-C because i last year AP-B physics was one of my favorite classes and i really enjoyed learning how the world around us works. Also applying the things that we have been learning in math for the past four years is really rewarding because finally there's a reason to learn it instead of just because the teacher says we have to in order to past the final.

    I am the kind of person who is better at Math than English and i always like science but didn't really find it interesting until last year in AP-B. Also right now my career of choice is an engineer, I don't know what kind yet, but this class will teach me things that all engineers must know which is one of the reasons I signed up for this class.

    This year i want to continue to learn how the world works especially electricity and magnetism because I find those the two most interesting topics that we covered last year. Also I hope to have fun in in this class while learning the kind of math/physics that engineers use.

    I am most excited about being a senior because it's our last year of high school and we get to have fun.

    I am most anxious about applying and selecting a college because it's a long process and I hate making decisions and I can barely think about it. Maybe I'll just apply early decision.
  16. 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.

  17. MrMuffinMan

    Free falling

    By MrMuffinMan,

    Afraid of heights? Well this guy isn't. Felix Baumgartner just made skydiving out of a plane look like a joke. In case you haven't heard because you don't get service or internet under the rock you live beneath, Felix just jumped out of a balloon 128,100 feet above the ground. Yeah that's over 24 miles. He also broke the world record for the fastest skydiver; reaching a velocity of 833.9 mph, faster than the speed of sound. I guess I have to talk about the physics behind this crazy stunt. If we look at it like we would of last year, neglecting air Resistance, vf2=vo2+2ax and in this case a is 32 ft/sec2 so if there was nor air he would be falling at 2863 ft/sec or 1952 mph or Mach 2.5 and I don't even need to know about impulse or momentum to be able to say for certain that's instant death. Plus if there's no air resistance, there's nothing to slow him down when he opens his parachute .Also it would only take him 89 seconds to fall that distance instead of the 4 minutes and 20 seconds. But since he didn't reach that speed and go splat against the ground, we can assume that there was air resistance on this day. Remembering the equation that we were "taught" in class F=bv and bvt=mg and since I don't know Felix on that level, I didn't feel comfortable asking he weight so we'll just have to use the average mass of an adult(175lb) to get b at about 4.6 lb/sec(gotta remember convert 833mph to 1223ft/sec). Of course there is error in all this because acceleration due to gravity isn't exactly 32 ft/sec2 24 miles above the earth surface and the force of air resistance increases as he gets close to the earth and the density of air increases but that requires a lot more information then i could find.
    http://www.bbc.co.uk/news/science-environment-19943590
  18. MrMuffinMan

    Gravity

    By MrMuffinMan,

    This post is all about gravity. All the review made it clear that I needed to work on Gravity.

    G-6.67*10-11 Nm2/kg2

    Fg=-GMm/r2
    Ug=-GMm/r
    (the negative means that gravitational potential is 0 at infinite distance)
    both of those are given on table

    g(or gravitational field)=GM/r2
    so acceleration of an object in orbit is GMe(6*1024)/(6.3*106+r)2

    velocity of an object in UCM since Fc=Fg
    mv2/r=GMm/r2 v2=GM/r v=(GM/r)1/2

    Total energy of an object in orbit

    E=KE+Ug=.5mv2+ -GMm/r= .5mGM/r-GMm/r=- .5GMm/2r

    Escape Velocity

    .5mv2=GMm/r v2=2GM/r v=(2GM/r)1/2
  19. 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
  20. 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.
  21. MrMuffinMan
    Anyone who was in class would of heard the great debate about a certain picture that seemed to be rotating different ways. But how can two people see different things while looking at the same picture. Optical Illusions are usually 2-D things that are pretending to be 3-D and since we see life in 3-D so our brain takes the 2-D image we're seeing and makes it into 3-D the reason why people saw the girl spinning in both directions is because she is spinning both ways, only at different times. But when we look at the picture we see it spinning one way, but girl is facing sideways, she instantly flips and starts rotating the other way. This tricks our eyes because our brain wants to continue to see her spinning the same way and the way this image is set up, it's almost impossible to tell which what she is facing when she's facing out of the screen. This picture shows how our brain sees how she is turning. And Charlie was wrong

  22. 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.
  23. MrMuffinMan
    Today is a beautiful day for a hurricane and since we have no school we all get to sit home and watch the hurricane bear down us on the radar. Looking at the Google earth we can all see that Sandy looks like a giant cloud with a hole in the middle that is spinning counter clockwise. But why? The answer is the Coriolis effect. Now what the heck is that? "In physics, the Coriolis effect is a deflection of moving objects when they are viewed in a rotating reference frame." This is saying that an object traveling "straight" like winds, on something that is rotating, such as the earth appear to curve when looking from the earth. So the Coriolis effect causes winds to deflect to the right in the Northern Hemisphere and left in the Southern. So when a low pressure system forms in the Northern Hemisphere, and air rushes to fill the area, the winds deflect to the right and cause the counter-clockwise motion to start

  24. MrMuffinMan
    F=q(v x
    R=(mv)/(qB) for a point charge in a magnetic field
    v=E/B (speed at which an object must be traveling not to feel a net force in a magnetic and electric field)
    T(torque)=NIA x B
    F=I(L x
    B=(uo)q/(4Pi)*(v x r^)/r2
    B=u0nI(for solenoids)
    B=u0*2I/(4Pi*R) (Due to single straight wire)
    B=u0*NI/(2Pi*R) (between the inner and outer radius of a toroid)

    Integral over closed surface of (B dA)=0
    Integral over closed curve of (B dl)=u0Ip

    r^=r/|r|
    Good luck to everyone tomorrow
  25. MrMuffinMan
    v=v0+at
    x=x0+v0+.5at2v2=v02+2ax
    F=ma
    F=dP/dt
    J=integral(Fdt)=change in P
    P=mv
    W=integral(Fdr)
    KE=.5mv2

    P=dW/dt
    P=F*v
    ac=v2/r=wr2
    T=F x R
    T=Ia(alpha)
    I=integral(r2dm)
    v=rw
    L=R x P=Iw
    K=.5Iw2
    W=w0+a(alpha)t
    ϴ=w0t+.5a(alpha)t2
    Fs=-kx
    Us=.5kx2
    x=Acos(wt)
    T=2pi/w
    Ts=2pi radical(m/k)
    Tp=2 pi radical(l/g)
    Fg=-Gmm/r2
    Ug=-Gmm/r
    Ug=mgh

    Part Two coming soon

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