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Everything posted by alf095

  1. alf095


    Speakers can cost hundreds of dollars to go with an awesome sound system but you can make your own as well. In order to do so you just need to learn the physics behind doing so. First electrical energy from the ipod tranfers and converts into magnetic energy which then converts to sound waves and hit against our ear drums which then converts again so we can understand them. A simple speaker can be made using a business card, wire, aux cord, a bowl and a magnet. Once you set everything up the cup in the bowl creates a louder noise and the cylindrical paper makes the noise clearer. Vibration moves up throufh the cords to the paper dishes and helps create sounds. To make everything sound better its usually better to put it on a very solid object for something to vibrate against. So next time you need a quick fix for a speaker, just use household objects.
  2. alf095


    When most people think of waves they think of the waves at the beach. But there are many different types such as sound waves versus microwaves. All together there are two main types, electromagnetic and mechanical. Radio waves would fall under electromagnetic since no medium is required. As you listen to the radio the channel you choose is determined by the frequency which is the amount of waves per second or 1/P. Compared to other electromagnetic waves, radio waves have a smaller frequency but a larger wave length. Wave lengths can be determined by measuring a wave from crest to crest which is usually done in meters. And since you dont need a medium for the wave to travel you can have a satelite in space send the signals all over.
  3. alf095

    Shooting An Arrow

    Archery has become a very popular sport in todays world. But in order to be great you must understand the physics behind it. When you draw back the string and anchor it in order toa im you are creating potential energy in the string. The more tension in your string allows for a greater potential energy. Once you release your string all that potential energy you had tranfers into the arrow as kinetic energy. Although its not as great as it could because some of the energy is also lost in friction from the arrow leaving the string. The force given through the energy as it launches across the room all transfers into the target leaving the arrow stuck. Again, this force isnt as great as youd think due to some of the acceleration being lost due to gravity pulling it down. The key to aiming the arrow is to aim hiring then intended target. As i said before, gravity pulls down the arrow. The path your arrow takes is parabolic so it will fall just a little bit in the end. The fletching on the arrow at the back creates for balance to keep the arrow straight which would occur for less energy being used in a path you didnt want. So next time you do archery, think of physics and you'll do better.
  4. alf095

    A Spinning Cat

    So my cat has a favorite chair he claims as his own, it's out swivel computer chair. He likes to get a running start to go jump onto it as you're walking towards it. His running starts allows for him to get a high acceleration which transfers to centripetal acceleration onto the spinning chair. In order for him to get a really good spin he needs a high velocity since he's already a big cat with alot of mass. With such a high acceleration and velocity his landing on the chair transfers some of the landing force making the chair move. But, he hasnt perfected this yet because if he was to perfect it then the centripetal acceleration would hold him to the back of the chair so he wouldnt move. But he needs his nails to hold on so he wont fall off so he needs some work to do. The only time his claws would be needed would be for an abrupt stop from his spinning. THe path he would take if this happened would be tangent to his path. Not only would it be tangent but it would also be a projectile path and take him a little ways away due to the force of gravity acting on him. But his nails prevent this by keeping him grounded onto the chair and absorb the force of the quick stop.
  5. alf095


    In the movie The Sorcerer's Apprentice the main character Dave is a "science nerd", which he is proud of. Very proud. He careated a device that when sparks fly out of a tower, music is created. At one point he even makes it so it plays a song by One Republic. He says it's because the speed at which the spark travels and hits another metal object and the amount of the coils around the tower creates the noise. This noise is also known as sound waves. This is one case where the movie is right in a way, usually movies aren't correct in their information. The coils he made are called solenoids, wires wrapped around an object, also the amount of coils and the thickness can effect the outcome of the sound wave. Sound waves have amplitudes and frequecnys like all other waves. But by changing the amplitude or frequency you can change the sound wave therefore change how it sounds. In the movie Dave does this by pushing a few buttons. In reality you can't change all of this by a push of a button that controls all 5 of his towers. You can't chagne everything by a push of a button, you need to change the actual medium of the wave which is where the movie falls short in what really happens. Also when he's in his metal cage hes holding on to a metal bar and becoming an actual conductor. But, what they dont show is him letting go because if he did so without grounding he would get a giant shock.
  6. When working at a pizza place physics is all around you. The pizza makers use a lot when rolling out the dough and making it fancy by tossing it into the air. As the pizza spins up you are using the centripetal acceleration and centripetal force. In order to figure out the force you use the equation F=mac so you must find ac with the equation ac=v^2/r. V represents the speed and r the radius of the dough. Also you must think of physics when you're just moving around the store. As you try to move and stop quickly you usually slide a little bit on the flour thats on the floor. To figure just how far you slide you would need to use your kinematic equations. Using your initial velocity and your final velocity, which would be 0 since you're not moving, you then need either acceleration or time to then solve for distance. Once you know your distance you will then know how far you will slide and can avoid running into something.
  7. Bowling is an activity that can be done as a sport or just for fun with a group of your family or friends. Some might not realize it but a lot goes behind the movements to make it work. First you have your potential energy in your starting stance. Right before you bowl most people begin in their stance to aim the ball or right before you wing it because you cant aim. As your arm swings down and you release the ball you are transferring your energy into the ball and convert the potential into kinetic energy. If you were to add up these two different energies you would have calculated your total energy used. Now, as the ball rolls down the lane about to hit the pins it doesn't seem to slow down. This is because the surface area being used has minimum friction so you can have the max speed possible. You're also supposed to follow through so you can give a greater force and have longer contact with the ball so you get a better outcome. So next time you go bowling you can realize how much work you're really doing.
  8. alf095

    The Wonderful Slinky

    Most kids play with a slinky when they were little. That is until it gets tangled and twisted then it's no fun.When you push a slinky down the stair or a pile of books you created as a path, it requires energy to do so like everything else. But the energy required for this to work is elastic potential energy or the potential energy of a spring. PEs for short has the equation of (1/2)kx^2. As you push the slinky down the path the length of the slinky becomes the x value. The x value represents the compression or amount of stretch the spring has. Next you just need to find the k, or the constant, when isn't as clear. In most equations the k is given to you but if you have to find it you can use Hooke's law which is Fspring=kx. You would then use your given x and the force to solve for the k. The amount of force you use and the amount of stretch your slinky has can change your potential energy.
  9. Snowball fights are a favorite for the cold weather. Many people complain through because they can't throw it or it'd be a weak attempt. Understanding physics could change that for many. For starters, you would want a 45 degree angle giving you the maximum distance possible. This was explained during the projectile unit earlier in the year. You must also follow through afterwards in order to give it as much force as you can. The greater the force applied can leave you to a better fight because it will help the ball fly. Plus, the follow through allows you greater contact with the ball which creates the force.
  10. alf095

    Physics of Sledding

    Sledding is one of many favored winter evetns. But, there's alot fo physics that goes behind it. For starters, the friction going down the snowy hill will be minimal due to the plasic on an icy surfact. THis will allow you to go much faster due to a lesser amount of friction. If you wanted to calculate the amount of friction u just have to remember "friction is fun" and use Ff=uFn. If you wanted to get the fastest speed you should also take into account your distance, start velocity, the hill slope and your total mass. A heavier mass will weigh you down but depenign on your other factors that could be a benefit and help you out. If the distance is long enough you could gain a greater acceleration but it will become constant after a while. Because you must take into account friction as your outside force, you will stop sooner then you thought but it'd still be best to stay away from objects in your way.
  11. alf095

    Physics behind Music

    Music is amazing and surrounds us everyday. At first it may not seem like physics is in music because come on, it's music. But because physics is well...everything...it has to be in music. Because music is sound you just have to look at the physics of sound. When you're blasting your music and you can feel the bass as its playing you're experiencing sound waves. These aren't your usual waves,this are compressional waves in which you cant see. If you've done certain math classes you may remember that there is more to compressional waves. These waves have a frequency to them which is how many times the waves go past a point and in a certain amount of time. Sometimes these waves are really short while others are really long! The short vs long is the wave length between the tops of the waves. And while the length between them can change, so can the height. The height of the wave is just referred to as the amplitude or an amp. When plugging your guitar into your amp, your amp just makes bigger sound waves increasing the sound that comes out so people can actually hear what you're playing.
  12. Being a middle child of 3, I've done my share of locking my brothers out of the house. You close the door, lock it, then race to the back door just in time to lock that as well and still get a chance to make a face at the one stuck outside. Quite the fun until you're the one locked out. Having done this routine recently, I started to think about all the physics that's behind this. For starters, by slamming the door your exerting a force onto it. The force I push onto it becomes a greater force then the force exerted from the hinges. Then the big race to the other side includes alot of accelerating if you want to be there first. With your initial velocity being zeros and all, you're going to need a higher acceleration then the person you're racing against. And as the person jumps off the porch to go faster you can easily calculate the distanced traveled while jumping using vi, vf, d, a, t, and your handy equations. You will have to do both a vertical calculation and a horizontal equation in order to do so that way you have at least 3 pieces of information which are needed when solving for d.
  13. alf095

    The Boo Brothers

    I never realized before how physics is everywhere until I started watching a movie. Most of the time cartoons dont seem to follow the rules of physics and it becomes obvious. While watching "Scooby Doo Meets the Boo Brothers", I realized Scooby and Shaggy dont really follow the physics when running from the ghosts or people. They kinda just decide to do their own thing like usual. So, Scooby and Shaggy jump up in the air, start running in air then zip off into the distance running away. But what comes up must come down. They should just fall back down due to gravity and no force pushing them forward. While the two are suspended in air the force of gravity (mg) acts upon them dragging them down. In order for them to rush forwards like they did they would need a force coming from the side to push them forward to where they were going. Plus they have no initial velocity so they're kinda stuck where they would be. Good thing they dont follow the world of physics.
  14. The method had such a high percent error due to many different places. One area could be a delay timing in hitting the button as you jumped and landed. Another coiuld be when reading the stick. Once you jumped you had to measure the difference but our group only measured the changed not the complete distance which is what you calculate with the formula.
  15. Breaking News Gravity! The young physicists at Irondequoit High School have calculated the acceleration due to gravity in a new experiment. To Find this they first measured the distance from the floor to the botttom of a ball. Then a person dropped the ball while timing it to figure out how long it would take. After three trials of this, they calculated the average of all three trials to find the accceleration. The students found out that the acceleration was 5.5m/s2. The accepted number is 9.81m/s2 and their percent error turned out being 43.9%. In the end the findings were considered inaccurate due to the high percent error. By: Abbey Fox, Mitchel Zachary, Spencer Donoghue
  16. alf095

    Physics of Biking

    Like many people, I don't usually think about the physics behind everything. But once i did think about it, there is a lot of physics when you go for a bike ride in Irondequoit. Going down St. Paul theres a slight hill, as you're biking down it you may not realize it but you are accelerating. To find acceleration you could take the longer way and find the velocity by taking the distance and dividing it by the amount of time you took getting down the hill. Then you can make a pretty graph and find the slope of the line or best fit line and boom, theres your acceleration. But when you come back up that hill, unless your a very athletic person, you start off at a constant speed and then slow down as you reach the top of that bill then go back to a constant speed when you level out. To find that constant speed when its all leveled you just need to solve the distance over time to get an average.
  17. Hey Paul, congrats on the eagle scout and I'm sure doing soccer will help you with some stuff in this class.
  18. Hello Amanda, we should play soccer some time soon before the snow hits and I'm glad we have physics together.
  19. Hello my name is Abbey. I am 17 years old but I will be 18 in October. I am in my senior year of highschool so this is my last year. I enjoy baking when I am bored as well as reading. Although I'm not good at it I also like to play soccer with my friends with our own interesting rules. I'm taking physics because its just kinda next in line for the sciences. I'm not real big on the whole science thing but my older brother insures me it was fun. I'm not really sure what I hope to learn this year but I'm sure it'll be something.

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