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zlessard

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Blog Entries posted by zlessard

  1. zlessard

    Hurricanes

    By zlessard,

    Sticking with the theme of natural disasters following my post on tsunamis, I decided to look deeper into the physics of one of the most frightening disasters: a hurricane.
    Starting off simply, a severe hurricane can have a power of 1x10^15 watts. To put that in perspective, that is about 3000 times the total electrical power generated in the entire world.
    Looking more at what happens physically, a hurricane starts when air rushes in to fill a low pressure system somewhere out over the ocean. As the air rushes in, the moisture in it condenses, which causes a release of energy which in turn warms the air. This warm air then rises and pulls more air in around it. All of this air rushing towards the center of the storm is sort of like a centripetal force, but this apparent force only occurs because of the motion of the earth. All of this moving air eventually picks up a counterclockwise rotation due to this apparent centripetal force. So all of this air rushing towards the center and in a counterclockwise manner is what gives the hurricane it's defining characteristic: the high wind. Hurricanes thrive over bodies of water, but die off once they reach land due to the lack of moisture. These massive storms are still able to destroy a lot on land before dying off.
    Hopefully, understanding these natural disasters will help me to remain as safe from them as possible.  
  2. zlessard

    Baseball vs Softball

    By zlessard,

    Yesterday I was talking with my friends and we started talking about pitching, as I used to be a pitcher myself prior to this year. We ended up discussing how the way softball pitchers throw does much less damage to your arm than the way a baseball pitcher throws. Because of this, softball pitchers are able to throw every game, while baseball pitchers throw once every 5 days or so, and I definitely understand how much a shoulder can hurt in the days following a pitching outing. It really made me wonder why throwing the ball overhand is so much worse for the body than underhand, so I wanted to look at the physics behind it. What I found actually shows that softball pitchers are at similar risk to shoulder injuries as baseball pitchers, but that is a product of overuse. The pitching motion is definitely safer and more natural for a human body to perform than that of a baseball pitcher.
    Softball pitchers are required to throw underhanded in fast-pitch games, so it is important that they do the windmill type motion with their arms in order to apply as much force to the ball as possible before releasing it. The whole time the ball is going around the "windmill", it is gaining acceleration, thus causing a faster pitch to come out of the pitchers hand. Pitchers also tend to rock slightly and lunge forward during their throwing motion, thus applying greater momentum towards the pitch. Applying all of these forward motions gives the greatest force to the ball in the "positive x-direction" and allows the ball to reach a peak velocity upon release.
    So much of physics analysis on baseball pitches involves what happens to the ball as it flies through the air. It's a true spectacle to see curveballs and sliders that baffle hitters to no end. But what I'm more interested in here is the motion of the pitcher. As a baseball pitcher throws, they generally have a sort of rock in their motion, similar to a softball pitcher but usually slower. After taking a short step back, pitchers lift their legs up high and then stride towards home. This high leg kick provides a potential energy to the throw, which gets converted to kinetic energy during the stride. During the stride, pitchers begin to bring all of their momentum forward as they come closer to releasing the ball. During the stride, many pitchers use the rubber mound to push off of with their back foot, similar to how a swimmer kicks off the wall in order to shoot forward with greater speed. This push off allows the pitcher to have even greater momentum moving forward as they throw the ball. Then, once they complete the stride, pitchers release the ball towards home plate. Young pitchers are told not to go through a motion with the same force as if you were throwing if you aren't releasing the ball, as this means that their is no force acting back on you as you release, thus causing greater stress on the shoulder. If you even replace the ball with a towel, you get that force acting back on you that allows your shoulder to proceed being healthy. This "equal and opposite" force is what Newton described in his 3rd law.
    So, upon analysis, although they look completely different, baseball and softball motions have certain similarities. They both apply as much momentum forward as possible, and release either directly above or below the shoulder. Stress on the shoulder in unavoidable in both situations, however softball pitchers are able to be used in much greater amounts. The thing I miss least about baseball, although I loved pitching, is the pain in your shoulder the days after pitching.
  3. zlessard

    Rob de Federer

    By zlessard,

    Not too long ago, I went to play some tennis against a friend of mine. Long story short, I won 6-2 despite the fact that he's a starter on the tennis team. What truly led me to my commanding victory was my dominant forehand and my supernatural ability to get on top of the ball. I even surprised myself with my ability to get topspin on the ball and still get it to go over the net. This inspired me to look deeper at the physics of the forehand. The spin on the ball is applied by sort of "brushing" the ball rather than hitting it dead on. The racket also must be tilted at an angle in order for the ball to go over the net and have as good of topspin as possible. The rackets themselves are actually of a material that is good for making spin, as they have a low coefficient of friction, allowing them to slip against themselves and generate even greater spin on the ball. Lastly, the force applied to the ball from the acceleration of the racket by my hand are what gives the ball such mind boggling speed along with the spin.  All of these factors put together are what lead to my deathly forehand return. 
  4. zlessard

    Shaq

    By zlessard,

    Last night, I watched a 30/30 (which is an ESPN documentary series that I would recommend to anybody) about the Orlando Magic, and one of the focal points of the documentary was Shaquille O'Neal, who was my favorite athlete in the world when I was a lad. If you've never heard of Shaq, he is a 7'1, 300+ lb basketball player. He was a force on the basketball court, for opponents and backboards alike. Throughout the documentary, dozens of clips were shown of Shaq shattering the glass on backboards or pulling down the hoop entirely, all of which occurred during games. This feat cannot be performed anymore because basketball hoops have been redesigned entirely in order to prevent this from happening. On the old hoops, the rim was only attached to the glass backboard, so if you could snap this off by applying enough downward force to it, you would shatter the backboard. This is something Shaq accomplished quite a few times. On the new hoops, the rim is actually attached to the beam holding the hoop up, so you would have to apply thousands of pounds of force to cause the rim to snap off and the backboard to shatter. On one dunk in particular, Shaq literally pulled the entire hoop down. The backboard did not shatter, but he pulled the entire hoop down. Shaq applied (estimated) over 1000 lbs of force (4450 N) in order to accomplish this feat. He admits that he did this on purpose in the documentary. 
    This feat is one that will never be replicated by a mortal, but it is fun to look back and see what such a massive individual was able to accomplish during a much simpler time.
  5. zlessard

    The Big 3-0

    By zlessard,

    I Googled "how much force is in a single keystroke" and I'm going to trust a source that says 12.9 N. This will help me in my overall (obviously hypothetical) analysis.
    Since this is my final blog post of the year I wanted to sort of wrap it up as well as possible and somehow tie in all of my other blogs. Using an online "character counter", I found out that there are a combined 50,015 characters across my 29 other blog posts, which have an array of topics ranging from pole vaulting to doomsday to Monte Alban. Not accounting for any backspacing, 50,015 is an accurate count of all of the characters I've put into these blogs. Utilizing the accepted force of a keystroke as being 12.9 N, that means I applied an accumulative 645,193.5 N to my keyboard for the purpose of these blogs. That's over 145,000 lbs of force, which seems like far too high of a number but I'm going to accept it regardless for the purpose of making this more interesting. I now wonder what type of things I could accomplish utilizing this much force that does not involve analyzing the physics behind a bladeless fan or a Mexican resturaunt.
    I could:
    Break 230 backboards (see blog no. 29)
    Throw a football very far
    Probably jump pretty high
    Write 28 blog posts and have enough left over force to perfectly emulate the biting force of an adult Great White Shark
    Push the ground really hard and pretend that the dent was caused by 32 1/4 Ford Explorers being stacked on top of each other. 
     
    As you can see, if I could somehow have concentrated all of the force that I put into the creation of these blogs into a single motion, then I could have pulled off some of the most incredible feats in the history of mankind. But alas, the people are left with 30 thoughtful, well crafted and occasionally humorous blog posts that will some day be hanging in a digital art gallery. Oh what could have been...

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