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About etracey99

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  1. This past week, we did a small partner lab. Our mission was to make a top out of the following materials: 2 paper plates, a plain wood pencil, 6 pennies, and tape. The top also had to be able to spin for more than only a few seconds. However, there were no instructions other than to make a top. Immediately, each student in the room with his or her partner immediately began undergoing the engineering process, whether they knew it or not. The engineering process has steps to be done in this order -- Define the problem, do background research, specify requirements, brainstorm solutions, choose the best solution, do development work, build a prototype, test and redesign. We already knew the problem, and we were presented with a top to look at in the back of the room, so we already defined the problem and did a little research on tops. The requirements were to make the top with the materials provided, and the top must spin for more than only a few seconds. We brainstormed quickly and then talked about our ideas on how to make the top. We then chose to mix our ideas together to get the best solution possible and we discussed who was to make it and walked through it together. Soon, we had a prototype and we were able to test that design. If it did not work that well, we tried something new. This lab, in a nutshell, was a little simulation of the engineering process! This lab also shows a relationship between tops, angular momentum and moment of inertia. As the top spins, the angular momentum generated points straight up into the air, and if there were no friction, the top would spin forever because the momentum that holds the top up is forever conserved unless acted on by an outside force. The moment of inertia of the top is the rotational analog of the mass of the top. The angular momentum discussed above is the result of the top's moment of inertia times the rotational velocity.
  2. Do billiard balls hurt?

    I will have to be more careful next time I play pool!
  3. This blog post was inspired by MyloXyloto's post: "Frisbee Fysics," Check it out! In football, throwing the ball with spin is called throwing a spiral. The better the spiral, generally the better the pass and the easier it is to catch. But why in football does spin make the ball easier to catch while in baseball spin makes the ball harder to hit? Well, in baseball, spin makes the ball curve. Different amounts of spin will make the ball curve at certain times or certain speeds, making the baseball harder to hit with bat. However, in football, the spin on the ball does not do that. When the football is thrown it immediately has angular momentum, and if thrown without being tipped or hit somehow, the football will remain in the same orientation. This is valuable because it makes the ball land in the receiver's hands quite easily because it will generally be caught the same way every time. In addition, because the football is in the same orientation throughout its entire flight, the ball will experience the same amount of air resistance and will therefore keep a straighter path. Imagine a football flying at you in a random pattern, and it is moving side to side slightly in the air. It will be hard for you to predict how and where to catch it compared to if the football was on a straight path right to you. In all, the importance of the spiral when throwing a football is accuracy! Tight spiral = quality pass.
  4. Frisbee Fysics

    You may have sparked an idea for a blog for me! Look for a spiral football throw blog!
  5. Elevators are Evil

    It is awesome that you were able to help him. Imagine helping him later in the year with something like capacitance!
  6. Archer's Paradox

    Whattttt... I have never even thought of that before! That's so cool. Also, +1 for the arrow pun
  7. Since I have a piano recital tonight, I have had music on my mind all day long. Seriously, I have practiced this piece for several weeks and now whenever I hear a piano, I think about the Maple Leaf Rag. Anyway, I have been thinking a lot about the chords in the song and how the different notes react with each other to make that chord sound the way it does. I have found some videos that show how different notes react with one another. Both of the examples compare C to every interval all the way up to the next octave. For both examples, see how the waves react when C is played with C# versus how the waves react when C is played with G because there is a big difference between the sounds of those chords. This first video is of sound in sine waves, which is most likely the most common and recognizable wave shape. This next video is similar to the last one, however, instead of sine waves they use saw waves. Saw waves are cool because they sound more futuristic/robotic and are extremely recognizable. A notable example of the use of saw waves in music is on Pink Floyd's "Welcome to the Machine" off of their record, Wish You Were Here. Saw waves are also prevalent in a lot of modern music, especially a lot of rap such as the beginning of Kanye West's "Father Stretch My Hands Pt. 1" off of The Life of Pablo right after the sample. (Very recognizable part of the song). I hope you enjoyed listening to noises for a few minutes. It is quite interesting how the different frequencies of the notes react with one another when put together!
  8. The Physics Behind Fidget Spinners

    I have never seen a cool way to use a fidget spinner.. until now!
  9. Mr. Guercio's Brick

    That brick is so agitating, way to figure it out:)
  10. Hurricanes

    Hurricanes are scary, but cool!
  11. Clay Matthews, 52 on the Green Bay Packers, is a famous linebacker. He has the all-time sack record for the Packers and has been in many commercials from Old Spice to Play Station. Let us look at some stats: Weight: 225 lbs (102.06 kg). Top Speed: 20.03 MPH (8.95 m/s) Imagine you are a quarterback, and Clay Matthews is running at you... You try to get out of the way but you simply cannot... all of a sudden... BOOM, you just got rekt because Clay Matthews sacked the snot out of you. How much force did you get hit with? Let's look. p=mv -> p=(102.06 kg)(8.95 m/s) -> p= 913.44 N*s. Clay Matthews, at top speed, has a momentum of 913.44 N*s. Now, let us suppose that from the first point of contact to the point that Clay Matthews has fully hit you, arms wrapped around you and everything, is about 0.15 seconds. (913.44 N*s)/(0.15 s) = 6089.6 N... Newtons -> Pounds = (6089.6)(0.224809) = 1368.99 pounds of force. Congratulations, your defensive line did not defend you and Clay Matthews has tackled you with 1368.99 pounds of force. Ouch
  12. Swimming is Newton's Sport

    Silly Jack, listen to Newton!
  13. Did you know that the average double door (two car garage size) is around 200 pounds? Imagine if every time you had to open the garage, you had to lift that much weight by yourself. Many people would probably not be able to lift their garage door if that was the case. The solution to this problem? Springs. Let us discuss torsion springs: A torsion spring is a spring that works by storing mechanical energy when it is twisted. Generally, 16'x7' garage doors are installed with torsion springs that must be turned 7 1/2 times, or 30 quarter turns. Twisting the spring this much puts enough energy into the spring so that when it connected to the door, the person will be able to lift it. Other doors have different springs that are meant for that size and type of door. Because of this, the garage door should only weigh about 7-10 pounds when a person lifts it because the spring is doing the rest of the work!
  14. This fancy looking device is called the Portal Gun. What does it do? Well, it is a gun that shoots portals -- one orange and one blue. If you shoot the portal gun onto two surfaces, lets say you shoot the orange portal onto the wall behind you, and the blue portal on the wall to your right, if you look at the wall to your right, you will see the side profile of your face looking at the blue portal. This is because what you see in the blue portal is through the perspective of the orange portal. What if you walk through a portal? If you walk through the blue portal, you pop out of the orange portal and if you walk in the orange portal, you pop out of the blue one! This would be an extremely useful tool, but is it realistic? I have seen two theories on the portal gun, let us begin with the wormhole theory: This is a wormhole, it is a theoretical passage through space-time. Imagine space-time being a piece of paper with two dots drawn on opposite ends of the same side of the paper. There are two ways to connect the dots that would result with the fastest route from one dot to another. 1) A straight line between the two and 2) folding the paper onto itself so that the dots are touching directly. A wormhole is the second option connecting from one dot to another or in the case of the portal gun, one portal to another. Would this work? Well if the portal gun could somehow create this circumstance, it is highly unlikely that a human would be able to walk through it because wormholes experience high instability, and it would most likely collapse upon itself. Wormhole = no good! The second theory has to do with Quantum Entanglement. Since I am not well versed on this phenomenon, let us just think of it as if you were born as a photon and you have a twin that you have been connected to for your whole life. Regardless of the distance between you, what happens to you will happen to your twin photon and what happens to your twin photon will happen to you (thank you Washington Post for providing an explanation close to that). So in portal talk, if the portal gun had the ability to entangle the particles of any two surfaces with one surface destroying whatever it touched and another surface recreating it, the portal could work. This would happen by your body being destroyed and put back together instantly by walking through the portal. In the process however, you would become a mirrored image of yourself, which would be fine and dandy if you do not mind being backwards, but the Quantum Entanglement would also mirror all of your chemical particles which would be no good. Simply walk through another set of portals and you would be returned to your normal, and safe, form. So could the portal gun work? If we master Quantum Entanglement, than yes. Otherwise, the portal gun is a fantasy that I am sure everybody would like! If you would like another explanation, please visit where I discovered the Quantum Entanglement theory of portal: https://www.youtube.com/watch?v=JzRvmNaPxdA&t=306s
  15. Linear* Momentum of the Earth

    What is the momentum of a train going infinity miles per hour?

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