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MrMuffinMan

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Blog Entries posted by MrMuffinMan

  1. 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

  2. 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
  3. MrMuffinMan

    Mind Trick

    By MrMuffinMan,

    As Dave said in his post, our computers class has been looking at this website called MindCipher.com. On this website there is a picture that asks, is she rotating left or right. I want to see what everyone thinks because our class is in disagreement in about this

    http://www.mindcipher.com/puzzles/25
  4. 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.
  5. 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
  6. 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.
  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

    Plasma Physics

    By MrMuffinMan,

    Plasma by definition is a highly ionized gas that usually occurs at high temperatures that conducts electricity and is affected by a magnetic field. But did know that plasma is the most common state of matter(if you don't count dark matter which hasn't been proven yet) Plasma is what makes up suns as well as lightning bolts and some regions of the earth's upper atmosphere. A plasma is composed of positive charged ion and free electrons but they're separate despite the attraction for each other. If they were to combine, the would turn back into a ordinary gas. In order to overcome the attraction of the charges for each other, there ether has to be large amounts of energy which is usually heat that keeps the particles moving too fast to combine or there is so much space between the particle that they can't combine which means they have low density. Here on Earth we use plasma to cut metals while on the sun, the plasma form of hydrogen combines to form helium and releases massive amounts of energy.
  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
    This was our second Independent Unit in a row and although I like the independent units a lot, I don't think have two back to back was a good idea. I know personally for me I just didn't have the motivation to get the work done and I found myself wasting whole periods. This left me with a lot of work to do last minute(hence the blogs at 11 at night). Also i feel like I don't really understand this unit as much as I do the other units, which is another result of my slacking. But we'll see how the test goes tomorrow. It's exciting to think that we only really have one more unit before the start reviewing for the AP but it's also scary realizing that in a couple weeks we're all going to have so much work to do getting ready for the AP.
  11. 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

  12. 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
  13. MrMuffinMan

    Work

    By MrMuffinMan,

    So this summer I will be working for a company called Lumetrics which is an engineering company that develops ways to measure very thing object without ever touching said object. They do this by using light and reflection of light. This technology is currently limited to transparent and translucent material but it's still really cool. By shinning a light into an object, some of the light bounces back at the first edge, some passes through. The light that continues through hits the back edge and more is reflected back. This difference in distance travel creates a phase shift which can be used along with the index of refraction of the material to calculate the thickness. I don't really understand works but I'm sure I'll learn all about it when I start work.
  14. 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

  15. MrMuffinMan
    With our last test we finished mechanics and official ended the first halve of the year. Surprising I didn't find the course as hard as I thought it was going to be. AP-B last year taught us most of the basics so we already knew most of the physics that we used this year. The major difference this year was the addition of calculus which isn't terribly hard compared to what Mr. Muz gives us. Also this year we aren't just given most of the equations and told to memorize; we are shown how to derive them and then expected to know the derivation as well as the equation. I'm a little afraid of Electricity and Magnetism because mechanics were easy to visualize which makes understanding easier for me, but when we're talking about tiny electrons, it's not so easy to picture. But hopefully it won't be too bad.
  16. 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.

  17. MrMuffinMan

    Maxwell's equations

    By MrMuffinMan,

    Gauss's Law

    Gauss's other Law
    Faraday's Law
    Ampere's Law

    We've already done the first one which isn't that bad and I hope they're all that simple. Although I think the second one means magnetic field though a closed surface is 0. And Faraday's law means something with E field is equal to the rate of change of magnetic flux. And i have no idea what Ampere's law is saying.
  18. MrMuffinMan
    x=v2sin(2theta)/g(when fired from the ground level)
    t=(2H/g)1/2
    y max=v2sin2(theta)/(2g)
    Fab=Fba
    W=change in KE
    W=Fdcos(theta)
    Vmax= urg1/2


    x=r(theta)
    v=r(omega)
    a=r(alpha)
    T=FRsin(theta)
    wf2=wo2+2(alpha)(theta)
    atotal=(ac2+at2)1/2
    KE=.5mv2+.5Iw2

    Parallel axis theorem
    I=Icm+md2
    moment of interia
    Disk= .5mr2
    Ring=mr2
    Rod(middle)=1/12ml2
    Rod(end)=1/3ml2
    Solid sphere=2/5mr2
    Hollow shell=2/3mr2

    SHM
    T=1/f
    x=Acos(wt)
    v=Awsin(wt)
    a=Aw2cos(wt)
    w=(m/k)1/2

    Springs in series
    1/keq=1/k1+1/k2...
    Parallel
    keq=k1+k2

    Pendulums
    w=(Mgl/I)1/2
    T=2 pi (I/mgd)1/2

    There will be another post on just Gravity and I did read about the LaTeX equation editor but i couldn't get it to work
  19. 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
  20. MrMuffinMan

    Pink light?

    By MrMuffinMan,

    The color that we see depends on the frequency of the light. Red Orange Yellow Green and Blue are the colors of light that we can see, so where does pink fit in? To find out, watch this video.



    How about that minus green flamingo
  21. 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
  22. MrMuffinMan
    In a very recent movie, a certain character purple suited character said the line "this is what happens when an unstoppable force meets an immovable object. While in the context of the movie, there was no unstoppable force or immovable object shown, what would happen in these two things really happened. But that the just the thing because all the fundamental forces are unstoppable and there is no such thing as a immovable object according to relativity. But what would a collision between an object that we can't stop and an object that we can't move. In both these cases the object would have to have an infinite mass that way any force applied to?this object wouldn't accelerate it at all. And so when they collided since they cannot be accelerated, the only thing that could happen is that they pass right though each other.



    ps
    What movie am I talking about
  23. 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
  24. 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.
  25. 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

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