# dspaker

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1. ## Physics of trampolines

Everyone loves to jump on trampolines. They are just so much fun! But do you ever think about the physics behind the fun activity? The physics involved in jumping on a trampoline is elastic potential energy. There is elastic potential energy because there are springs all around the trampoline. Elastic potential energy is equal to one-half times the spring constant times the amount of compression squared. To find the spring constant or the amount of compression, you must know the other and the force of the spring and plug it into the spring force equation which is Fs=kx. Once you know both k and x, you can find the amount of energy stored in the springs by plugging them into the elastic potential energy equation. Now you can figure out how much energy is stored in a trampoline before you jump on it!
2. ## Physics of skydiving

Skydiving is something that I've always wanted to do but apparently you have to be 18 years old to do it so I will have to wait until the summer. However, I think it would be fun to talk about the physics of skydiving so that I can fully understand it when I eventually do it. Some of the physics involved in skydiving are free fall, kinematics, drag and the force of gravity and air resistance. Skydiving is a free fall from a plane so in order to find final velocity, the height or distance of the jump or the time taken to complete the jump, one can use the kinematic equations. It is important to remember that gravity is equal to 9.81 m/s^2 and the initial velocity is 0 m/s. The forces acting on the jumper are the force of gravity and air resistance. The force of gravity is equal to the jumpers mass times the acceleration due to gravity. Air resistance is the force that is pushing up on and working against the jumper. Drag is involved in skydiving because the jumper uses a parachute to slow his fall and it creates an upward force because the air resistance works against it. As you can see, there are plenty of physics that have to do with skydiving.
3. ## Physics of bobsledding

Another one of my favorite Winter Olympic sports is bobsledding. Having done it once before I can say it is extremely thrilling, though I was not thinking of the physics involved at the time. Perhaps if I do it again I will be able to apply all of the physics I have learned. Some of these include friction, drag and momentum. There is almost no friction between the sled and the ice underneath. The sled has really thin runners that help to make it travel faster but it also means that it is very hard to steer. Drag is involved in bobsledding because it is created when air passes around the sled and slows it down. Drag can be minimized by designers making the sled as aerodynamic as possible. Momentum is involved in bobsledding because the momentum of an object is its mass times it's velocity. The more mass and the faster the bobsled travels, the better chance they have of winning. This is why it is important for them to have a good push off. Physics are really important to the sport of bobsledding because there are a lot of factors that contribute to a good bobsled run and they can all be figured out with physics.
4. ## Physics of speed skating

To continue with the the theme of the Winter Olympics, I will talk about the physics of another one of my favorite events, speed skating. Speed skating is exciting to watch, but do you know how fast the athletes are actually going? They can reach speeds of up to 62 kph which is almost 40 miles per hour! Some of the physics of speed skating include centripetal force, work and power. Centripetal force, which is equal to the mass of the skater times their velocity squared divided by the radius of their circular path, exists when the athlete is skating around a circular path and their centripetal acceleration is in the direction of the center of the circle. Work and Power are involved in speed skating because power is the rate at which work is done. Speed skaters generate a lot of power when they reach the really fast speeds of 40 mph. When I watch speed skating I will be sure to think of all the physics involved.
5. ## Physics of the ski jump

With the Winter Olympics approaching, I thought it would be appropriate to discuss the physics of a few of my favorite winter sports. My first favorite is the ski jump. The 2014 Winter Olympics is the debut for the women's ski jump. How exciting? Some of the physics of the ski jump include kinematics and gravity and ramps and inclines. The skier jumps off of a huge ramp and flies through the air until they touch the ground. There is friction that occurs between the skis and the ramp while the skier is accelerating down the ramp. The force of gravity is present throughout the jump but it is the only force acting on the skier after he or she leaves the ramp. Kinematic equations can be used to find the velocity, horizontal or vertical distance, acceleration or time of the jump. The force of gravity on the skier can be found by multiplying the mass of the skier by their acceleration. As you can see there are so many ways to apply physics to fun things.
6. ## Physics of driving (as in golf)

That's very interesting. I've never thought about it that way. Nice picture too!
7. ## Catapult Building

I had so much fun too. The 45degree angle is very important. Your catapult is very cute though!
8. ## Physics of riding a Zipline

The physics of zip-lining are very important because it is an activity that can potentially be very dangerous. When zip-lining, the line must be somewhat angled down so that the person can actually zip down the line. There is friction when pulley glides along the wire. The rider accelerates when the force of gravity pushes them down the line. The extra friction that occurs when the rider pulls down on the line to break results in a decreasing velocity and a negative acceleration. The next time you ride a zip line be sure to think of all the physics involved.
9. ## Physics of skiing

Physics is all around us, even in skiing! For example, there is friction between the ski is and the surface of the snow due to gravity pushing down on the skier. When starting from rest, the skier accelerates down the slope as a result of gravity. There is air resistance known as drag which slows the skier's velocity. This is extra clothing which is exchanged for a slim suit which is worn by racers. I can't wait to ski this winter and be able to apply all of the physics to my favorite activity.
10. ## Physics of swimming

Physics is all around us but it is very easy to see in swimming. For example, when someone is diving off the block, it can be seen as a kinematic equation problem. You can find the horizontal velocity and the time that they are in the air. You know the vertical distance of the block so you can find the launch angle. You could also find the point at which they enter the water and how long it takes them to reach the maximum vertical distance. The next time you dive into a pool, you should think of all the physics in what you're doing.
11. ## Physics in Softball

That's a very interesting way to look at softball.
12. ## Intro to physics

I am a student current regents physics student. I am on the swim team and enjoy riding my bike and playing with my dog. I am strong in mathematics and social studies. After high school I plan on going to college. I am taking physics because my counselor recommended it and it was the next class for me to take. I also wanted to take a fourth year of science because colleges like to see that. But apart from those reasons, it just looked fun. This year in physics I hope to get a good grade, do a lot of experiments and have fun. I am very excited to make catapults and bottle rockets later this year. I am also excited to learn how physics applies to my interests and the rest of the world around me. I am anxious about the tests this year because I am not a very strong test taker, but luckily Mr. Fullerton has a unique way of grading tests and doing test corrections and I know that i will succeed.
13. ## Myself and My Interests

I think Physics will be really interesting too. Mr. Fullerton seems like a really fun teacher