Sunday, May 17, 2015

Top Ten Places You Can See Physics At The State Track Meet

Over the weekend I went to the state track meet and saw a whole lot of physics!...

1. We drove to the meet in a bus. The bus is powered by a motor. The motor is supplied voltage from a battery which supplies current. The magnet supplies a magnetic field that makes charges move. The wires spin as a result of this current. The motor functions because there is a current carrying wire that feels a force from the magnets magnetic field and a torque is caused.



2. At the meet when people crossed the finish line they kept running for a bit before they slowed down. This is because of Newtons First Law which states that objects in motion stay in motion unless acted on by an outside force. In this case the runners are moving very fast and their bodies want to continue to do so. Because of this, even though they have crossed the finish line they keep going foreword while creating a lot of friction on the track until they stop.
The girl on the left is still running. 
I have crossed the finish line but continue to move
Emma has finished and stopped moving.

3. At the meet, people compete to see who can run at the fastest speed. Speed is the measure of the distance an object, or in this case a runner, travels in a designated amount of time. For example, my 4x800 team travelled 3200 meters at a speed of 10 minutes and 44 seconds.
My 4x8 team.

4. We can also measure how fast someone ran by using velocity. However, we could only use that measurement on the straight parts of the track because velocity requires a specific direction. If someone asked, "what was the velocity of that runner in 800?" you would say, "well, they rounded a curve which is not traveling in one direction so we can't measure their velocity". But if someone asked, "what was the velocity of that runner in the 100?" you would say, "well, they traveled in one direction so lets use the equation, v=d/t to find out".


5. We could also measure acceleration at a track meet. Acceleration is how fast an object picks up speed. We can measure this using the equation velocity/time.
Holt is accelerating by slowing down.
Rylynn is about to accelerate.

6. At the meet there was also long jump which is an example of projectile motion. The athlete jumps of the ground, sails up and then comes back down to the ground, trying to cover the longest distance. Lets say the jumper wants to cover 18 feet and jumps at a 45 degree angle. We can use the formula v=d/t to find the horizontal velocity. We can use the formula d=1/2gt^2 to find the vertical velocity. In order to find how fast the person was moving at any given time we use the pythagorean theorem.
Hank is in projectile motion.

7. In pole vault, once the athlete clears the bar, they fall down. This fall down is an example of free fall which is when an object falls due only to the acceleration of gravity. We can find out how far they fall/how high they jumped using the formula d=1/2gt^2. We can also find out how fast the person fell we can use the equation v=gt.
Elliott is about to free fall.

8. We can use Newtons Third Law and action and reaction pairs to understand how someone runs. Whatever force the person pushes back on the earth, the earth will push foreword that equal force. The person who pushes back harder on the earth will move faster.
Runners push ground, ground pushes runners.

9. Durring the track season I got a leg injury because I often ran on the hard track as opposed to the softer dirt trails. As we know from Newtons Third Law my foot goes from moving to not moving regardless of what surface my foot hits. Therefore my foot will have the same change in momentum regardless of the surface. Although my foot will have the same change in momentum, it will have a small amount of time to go from moving to not moving and therefore a large force on the track. On the trails, my foot will have a longer time to stop moving and therefore a small force so I will have less injury on the trails.










10. At the meet we ate sandwiches. The coaches used a credit card to buy those sandwiches. Credit cards work because of electromagnetic induction. In the credit card machine there is coils of wire. When the magnetic strip on the card goes through the colds, the magnetic field in the coil is changed. This induces a velocity which causes a current. This current sends a signal to the computer and allows the card to pay.


Go Blues!






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