• Content count

  • Joined

  • Last visited

Community Reputation

0 Neutral

About ajgartland22

  • Rank
    Advanced Member
  • Birthday
  1. (49 short days until game #1) Today was a very eventful day in the baseball world. Spring training started and Hannah and Derek Jeter announced the birth of their first child. To celebrate both, I thought I would break down the physics behind two of Derek Jeter's most iconic defensive plays. The first play, commonly called the "jump-throw" is known across the world by almost any baseball player or fan. It starts with a sharply hit ground ball towards the hole between Jeter and third base. Looking at simple kinematics- based relationships, it is a large feat in itself for Jeter to be able to intercept that ball by moving as far and as fast as he did. Next, he calculated the exact flight of the ball as it hopped into his glove, and then with the full momentum of his body taking him away from first base, unleashed a powerful, incredibly accurate throw that beat the runner and ended the inning. Critics say that the only reason that play was made was because Jeter didn't have the speed to get to balls hit away from him, but nobody can deny the fact that the throw, made perfectly, despite the fact he was traveling at a constant speed away from his target and being accelerated back to earth by gravity, is one of the greatest of all time. Another iconic Jeter play, made in a pivotal playoff game against the Oakland A's shows just how good of a physicist Jeter was. The play began as a defensive error by the right fielder. He made an awful throw trying to get the tying run out at the plate. He missed the 1st baseman who was supposed to relay the throw home, and instead sent it sailing into the grass by the 1st base dugout. All of the sudden, Derek Jeter came streaking across the field, and on a full sprint fielded and backhand flipped the ball to the cathcer, Jorge Posada, who nailed Giambi with a quick swipe tag to preserve a 1-0 Yankees lead. The physics come in when Jeter released the ball. Travelling at over 15 mph, Jeter knew exactly what vertical and horizontal angle to launch the ball at in order for it to be delivered to Posada to enable a smooth tag. In the video, one can clearly see how the ball seems to curve as it is being delivered to Posada. This is because the ball is moving in all 3 directions at once. It is moving forward with the force of Jeter's "push", sideways with the constant velocity supplied by the sprinting body, and downwards due to gravity. By correctly judging all three of these factors and many more, Derek Jeter was once again able to make himself into baseball legend with the flash of his glove and the flick of his wrist. Here is a video of some of Jeter's best defensive plays. It starts off with The Flip and his Jump-throw is at 2:44.
  2. 56 days.... Getting hit by the ball in baseball is just a fact of life. Many plays in a game consist of players simply knocking the ball down with their bodies in order to better control it or keep it from getting past them. Usually the ball impacts a part of the body that can take a good amount of force without too much pain (like the torso). Rarely, and usually by error of the fielder, the ball can find its way to less ideal areas of the body. In my case, playing the awkward bouncing grounder on old indoor turf the wrong way resulted in the ball settling on a spot right in the lower part of my forehead. When the batter hit the ball, it took one high hop and I moved backward to catch the ball at the apex of its second hop. When the ball hit the ground after the second hop, its rotational velocity was very high, and the turf provided the perfect surface for the ball to grip the ground and convert that rotational energy into translational energy, therefore increasing the speed of the ball. I was not ready for this sudden speed increase and so when the ball got to me the glove was to low, so it bypassed my glove and continued straight into my face. Currently on my forehead, one can see the stitches imprinted into my skin and also broken skin where the speed at which the stitches were rotating caused them to damage the skin in certain places. Using physics to think through the situation helps me understand why that second hop on artificial turf is always so annoying.
  3. 62 days until the first Varsity Baseball game of the season (@ Arcadia if anyone's interested) My job is a pretty simple one: I work behind the snack bar counter at Lakeshore Hockey Arena and cook food for anyone who cares to buy it. Its not hard and can be fun depending on who you work with but there is one thing that really aggravates me: the french fry bags. The bags have perforated tops to make opening and pouring the fries out of them easy. A major drawback is made very clear though when you open a new case of fries you try to pull the first one out. The boxes they come in should really only hold maybe 5 bags of fries but instead come jammed with 7. All of these bags scrunched together, paired with the fact that the only way to pull them out of the box was by grabbing the (perforated) tops of the bags, what would frequently happen to me was I would tear the top off of the bag, opening the fries in the process of taking out of the stock freezer. This made my boss very upset every time he noticed a bag of opened, freezer burnt fries sitting in the snack bar freezer. To save myself from my boss, I tried to think of how I could possibly grab fries without ruining a whole new bag... Then one day instead of grabbing the first bag in the box, I grabbed the middle one and it came out perfectly. It had dawned on me that maybe the rough cardboard at the end of the box was causing more of a frictional force on the bag than the perforation could handle. I tested this theory one day by grabbing a bag from the middle of the box- one that was surrounded on both sides by smooth plastic bags which had a smaller coefficient of friction and therefore less force than the cardboard- and since that day I have been grabbing from the middle and my boss isn't yelling at me anymore. So use physics- it makes your boss happy.
  4. this connects to when I go camping I was always told to drink liquids near my body temperature bc that way the body expends less energy making the liquids a manageable temp
  5. Its cool to think about how the energy is transferred into the glass from the bullet
  6. really interesting take on a really exciting movie!
  7. I wonder where this technology will take weaponry in the future
  8. A small yet very important technique in baseball is a player approaches, touches and leaves a base during a play. The idea is, from a physics perspective, to translate as much kinetic energy as possible around a 90 degree angle in order to continue to the next base with a large amount of velocity. The major part of the technique happens before you even touch the bag. During the approach, the runner must bend away from the baseline and then come back to the base in a way that makes the turn longer and less of an angle. (watch the video it this doesn't make sense) What longer distance the runner must travel is easily made up for by the burst of speed he gets when he pushes off the inside part of the base with his right foot. Contacting the inside of the base with his right foot allows the runner to line his body up perpendicular to the face of the base and really push off of the raised base to use Newton's 3rd law to his advantage. Looking at this from a kinematics perspective, one can see that the increased velocity, coupled with a more direct route to the next base greatly increases the likelihood of reaching that base safely. In the video below, go to 1:00 and look at #47, Howie Kendrick. Although this is an amazing throw by Cespedes, it is one Kendrick could have easily score on if he had rounded third correctly. You can see that he is many feet away from the 3rd base line which means he rounded 3 at a speed that was too great at too sharp of an angle. This curved route meant he probably had to run 5 or 6 feet more than the actual 90 feet that separates 3rd and home. A better turn means he is safe without a doubt.
  9. I have been wanting to do a post on the physics behind a fastball for a while... and because of the events that transpired early today I think this is a fitting time to do it. Today, Yordano Ventura, 25 had his life taken in a car crash in the Dominican Republic. He was a pitcher for the Kansas City Royals and was widely regarded as a pitcher that most announcers describe simply as "electric". Usually I use physics here to bring to light how truly difficult baseball is and the skill of the players who compete for a living. But as someone who has watched Yordano, I can say even physics have trouble doing his fastball justice. With fastballs that easily get up to 100 mph, it can be calculated that in just .41 seconds, his pitch goes from in his hand to into the catcher's glove. As a comparison... an average blink is anywhere from .3-.4 seconds. W:hen Yordano pitched you could almost literally say: "don't blink, or you'll miss it". Added to this is the fact that by using the magnus effect to his advantage, Ventura's fastball moves from left to right and even seems to rise, defying gravity. Any abover- average major league hitter can destroy a straight, 100 mph fastball, but almost nobody can put that same power on a 100 mph fastball that is moving side to side and seemingly against gravity. Here's a video of Yordano Ventura pitching in the biggest game of his career: Game 6 of the World Series. He said he was pitching this game for his late countryman Oscar Tavares, another young, promising athlete who himself had died in a car crash.
  10. This past semester I took "History of Warfare", a half-year elective that took an in-depth look at all major US wars since WWI. On the last day of the class, we shifted focus to the homefront and talked about mental injuries veterans sustain and how they try and cope after war. One thing that really shocked me was the existence of a fairly recently discovered injury called Traumatic Brain Injury (TBI). What surprised me even more was the way in which this injury was sustained. Essentially, the supersonic winds created by explosions cause the brain to rock inside the skull over a time period of about 3 milliseconds. What is amazing (and very concerning) is the fact that these winds can impact anyone in the blast radius of 1 foot to up to 1 mile. The brain even moves so fast that your body doesn't even know its happening... and because of this it is an injury that over 200,000 living veterans suffer through every day. The symptoms can be compared to CTE in football players and leave veterans feeling "punch drunk" just like the worlds most famous boxers. The physics come into play when the blast wind hits the body. First off, the shock of the wind is transmitted to the body as a wave of energy and any surface (like a skull or helmet) can reflect the wave, meaning it can impact the brain 3-5 times per explosion. In WWI, when the symptoms were first being documented, leading doctors thought the kinetic energy of the blast traveled up the spinal column and into the brain. Now, there a are theories that go so far as to say shock waves of kinetic energy can reach the brain through the bloodstream. Although the injury is very serious, it is interesting from a physics perspective to think about the energy transfer happening between those billions of particles through the bloodstream, spinal cord or skull. P.S.- Anybody with a free period should see if they could get into this class for the new semester. Its an eye-opening class that was definitely a great choice of an elective.
  11. A new development in baseball, especially in Little League, is the implementation of breakaway "safety" bases that rely totally on friction with the ground to stay in place. The idea behind them was that younger players, who had not yet perfected sliding, were getting hurt when they slid into a immovable base and hurt themselves from the sudden deceleration of their body. With their leg (mostly the knee and ankle) bearing the brunt of that force, it would make sense to take every precaution to prevent potentially career altering injuries at such a young age. The key to breakaway bases is the low coefficient of friction that the base has with the anchor it sits on. This property allows the base to slide off of its platform with the player, decelerating him over a longer time and distance, therefore reducing the chance of injury on a slide. Simple yet effective innovations like these make the games we love to play a lot more safer and enjoyable for people of all ages and skill.
  12. I always wondered why people do that ^ but now it makes sense
  13. Lebron has legs that are perfectly capable of pushing off the ground too... I dont know if there is a law of physics saying only Draymond Green can add momentum to a system.
  14. I thought I would do a quick post about some very interesting information I read about pitching and how it ties in with bio-physics. As a lot of people know, Tommy John surgery is a dreaded operation that is used on mostly baseball players to correct the mother of all baseball injuries: a UCL tear. The UCL, or Ulnar Collateral Ligament is a small ligament on the "pinky side" of your elbow. Its main purpose is mainly to hold back all the torque generated by your arm when it goes into a whipping overhand motion. Basically, its a convenient little piece of tissue tailor made for all of us throwing sport athletes. The weird (and kind of scary) part is, for how much throwing revolves around this ligament, us humans punish it all the time. In fact, multiple studies conducted among college and pro baseball pitchers have repeatedly shown that the UCL sustains anywhere from 65-70 Nm of torque on any given pitch. And the point of complete failure for a UCL in a lab? A mere 35 Nm of torque... In other words, every throw, athletes can be putting up to DOUBLE the amount of stress on their UCL than what it takes to completely snap it. Although this is a scary thought, one may wonder, "this must all not be true because I've never had an UCL injury before". And although that statement is true, it raises another very valid point: mechanics. The only reason the MLB does not see an average of 1 UCL failure per pitch is because of attenuation. Basically the whole reason you twist your core, drive with your legs and tuck your opposite arm when you throw is to attenuate the torque on your elbow. To put it simply, all of your body parts "help out" your elbow and contribute in their own way to driving the ball forward, meaning the velocity of the ball does not depend solely on your elbow and therefore all that 70 Nm of torque will not be put directly on your UCL. So remember kids: attenuation is what is saving you from a career ending injury... so practice those mechanics!!
  15. Thank God I'm a Clemson fan... Saturday was an awful day for me watching the Raiders fall to the Texans; but Monday was a different story. My Clemson Tigers won the College Football Playoff Championship with a thrilling victory over Alabama. It was one of the most exciting games I have ever watched and was definitely well worth staying up till almost 1 on a Monday night. Although I could talk about the physics of Deshaun Watson holding up the National Championship Trophy, that would be a little too similar to my last embarrassment of a blog post. Instead I want to talk about the rotational velocity of Deshaun Watson during one especially big hit put on him during the game Monday. As I was watching the game and I saw Watson helicopter through the air, my first thought wasn't: "Is he ok???" It was more: "Hey! what a great idea for a blog post!" So here I am, about to calculate the rotational velocity of Deshaun Watson. As you can see by watching the video of the hit below, Deshaun was sent into the air and from hit to re-contact with the turf, his flight took approximately one second. He rotated almost exactly 1.5 times and therefore, using rotational kinematics, we can find that he was rotating at over 9 radians per second. Converted to rpms and that would equal 90 almost exactly. Now most people cant put 90 rpms into context, so here's another way to look at it: Deshaun Watson is 6'3", which means layed straight out, he forms the diameter of a circle that is 75" long. When calculated, the circumference of that circle is 235.7 inches, and knowing that his head and feet traveled 1.5 circumferences, we can calculate that his body parts on the outer edge of the circle whipped around at 19.9 feet per second. Converted to mph, thats 13.4 miles per hour! That may not seem like alot but just imagine sprinting at someone and colliding helmet to helmet at over 13 mph. That wouldn't feel too good! This is exactly what could have happened to Deshaun's head but with the additional force of that other person- running at speeds of up to 20 mph- exerted on his head. Although I know the math is far from perfect, thinking about football through physics like this makes one appreciate how these athletes put themselves on the line for the games they love.