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About jrv12

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  1. Stranger Things

    It's crazy to think that an alternate dimension could actually exist!
  2. Physics of Fetch

    A dog trying to catch a ball in its mouth is like a person trying to catch a football, a lot of coordination and timing. Kinematics could be involved to find the distance, but there is not enough time for a dog or person to calculate that since it only takes a couple seconds for the ball to reach the dog. However, if you ever did want to find the distance, you would need both the x and y components of the initial velocity, acceleration in the y which is equal to 9.8 m/s2, and the time it takes for the ball to reach the dog. It would be a little more complicated than a simple kinematics problem since there is the height of both the person and the dog to take into account. When I was in Target the other day, I saw a new toy called the Chuckit which is basically just an extension of someone's arm that you can put a tennis ball in in order to throw it farther. Using the equation torque=Force*radius, the Chuckit increases the length of someone's arm and therefore the radius. By applying the same amount of force, the person can throw the ball much farther by using the Chuckit because of the increase in torque. So, if your dog isn't getting enough exercise from you just throwing the ball, add more length to your arm to throw it farther!
  3. Why I spent $250 on a Swim Suit for Sectionals 2017

    I always thought that Daniel was crazy when he shaved his legs during swim season but it does make sense since it gets rid of drag!
  4. More Weather... Lightning!

    That thunderstorm we had the other day was certainly crazy!
  5. I'm sure everyone has heard the myth that if a penny is dropped off the Empire State Building it could kill someone. Well, fortunately you can still walk in NYC without shielding your head from falling pennies because this is not true. The penny will tumble as it falls which will slow it down, and because pennies are flat and thin, they experience a lot of air resistance opposing the force of gravity. A penny would reach a terminal velocity of a meager 25 mph at 50 feet. Instead of going straight into your head like most people believe, the penny would bounce right off and you would most likely only feel a small sting. If air resistance didn't exist, the penny would reach 208 mph by the time it reaches the ground, which could definitely do some damage. However, don't go walking around without your head covered just yet. A pen that is dropped perfectly vertical from the skyscraper would reach a terminal velocity of 200 mph, and would most likely kill you. Because of the narrow, cylindrical shape of the pen, it would fall like an arrow and pierce your skull, killing you. Now, if you're like me, you will want to walk around with a helmet on for the rest of your life in order to avoid a hole in your skull from a stray pen!
  6. Mr. Guercio's Brick

    I always somehow manage to trip over that brick when walking out of the classroom!
  7. Physics of Angry Birds

    While the once popular cell phone app reached its peak a couple of years ago, Angry Birds is a great example of projectile motion. The basic goal of the game is to launch the birds using a slingshot to knock out the green pigs. In order to knock out the pigs with the least amount of shots, you need to launch the birds with the correct initial velocity and at the correct angle. There are multiple different birds that are used in each level, including the standard red bird, a blue bird that turns into 3 birds when tapped, a yellow bird that changes to a faster velocity when tapped, a white bird that shoots down an egg when tapped, a black bird that blows up when tapped, and a green bird that turns into a boomerang when tapped. If we only look at the standard red bird, we can infer that the app does not take into account air resistance since the bird follows a parabolic path. Therefore, the horizontal component of the velocity stays the same and the vertical component of the velocity changes because of the acceleration due to gravity. The kinematics equations vf=vi+at , x=vit+1/2at2 , and vf2=vi2+2ax can be used to solve for the distance the bird will travel both vertically and horizontally using given variables. In order to cause the greatest damage, it is best to pull the slingshot back as far as it will go in order to have the greatest initial velocity and travel the greatest distance. Now playing Angry Birds should be much easier considering the projectile motion we have learned and how to calculate the correct initial velocity at the right angle in order to get the bird to travel the correct distance! While you most likely won't do any actual calculations, your estimations should be much closer and will hopefully help you get a higher score!
  8. How to (Properly) Tune a Flute

    This helped me last year too! I finally learned why we have to pull out/push in the head joint if the flute is sharp or flat!
  9. Do billiard balls hurt?

    Put simply, the answer to this question is yes. But here's how I found out: The other day, I was playing pool in my basement with my brother and, of course, I was looking at something on my phone just as the cue ball was hitting the 9-ball and he applied so much force that the 9-ball bounced off the table and landed right on my foot. It hurt really bad and I still have a large bruise right on the top of my foot. Well, since a standard billiard table is .762m and we can use acceleration as 10m/s2 and the billiard ball started from rest from the top of the table, the final velocity that the ball hit my foot with was 3.9m/s. Ouch. A billiard ball's mass is .17kg, so the force that it hit my foot with was 17N. Ouch. Needless to say there is a large bump on my foot from the ball and now I will always pay attention the playing pool with my brother since he clearly doesn't understand physics well enough to be able to hit the ball with enough force that it will still move, but not too much force so that the ball won't end up on the ground.
  10. The Physics Behind Fidget Spinners

    I've seen that episode of Dude Perfect because my brother made me watch it and it's so cool!
  11. Momentum in Sports

    The first point of sectional finals, we have serve. Ace. A couple more aces and a big serving run and we are now up 18-3. We end up winning the first set 25-6. 25-6. 25-6, in sectional finals, against Pittsford Sutherland. It is clear now who has the momentum moving forward. The momentum from the first set carried us in the next two sets and we end up winning the match and sectional finals. In a sport, when a team has the "momentum" in the game, it means that they are the ones on the move and will be hard to slow down and stop. In physics, momentum is the product of mass and velocity, and the equation is p=mv. Therefore, as mass or velocity increases, so does momentum. Momentum is also a vector quantity, so it has a direction to go along with the magnitude. A change in momentum is the impulse which uses the equation J=Ft. It would take a large amount of force in a large time to create a big impulse or change in momentum. Last night, Sutherland started to create an impulse in the second and third set, but it wasn't enough to sway the momentum in their direction. Here's a video of the final point of the match last night!
  12. Newton's Second Law Lab

    Now we know that it won't be perfect and there will be error!
  13. I Drop Everything

    I drop everything too! Most of the time I just let it fall and hope nothing breaks!
  14. Most people have made oobleck at some point in their school career, whether it was in elementary school as a fun project or in high school to demonstrate physical properties. How did oobleck get its name? From the Dr. Seuss book Bartholomew and the Oobleck. This simple, non-Newtonian fluid made from a mix of cornstarch and water defies Newton's Law of Viscosity. Oobleck magically transforms (well, not magically, but it seems like it!) from a liquid to a solid with the slap of a hand, punch of a fist, or kick of a foot. Because of the shear-thickening behavior of oobleck, a greater applied force leads to a greater resisting force from the fluid and it behaving like a solid. Without an applied force, the oobleck will behave like a liquid. The behaviors of these shear-thickening fluids allow them to be used as body armor since they offer great flexibility and ease of movement, but would resist a sudden force such as a bullet or knife. Watch this video if you've ever wondered how to walk on a liquid:
  15. Diffusion of Responsibility

    I remember this from AP Psych last year and it definitely still applies to most classes!

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