My Top Ten Physics

Here's to the very last physics blog post I will probably ever do in my entire life. *Cheers* 

The very last blog post criterion says that we should create a condensed version of this year’s lesson into our top ten. Top ten lists can be the best, the worst, or for me a combination of both in regards to what we’ve learned.

At the beginning of the year in my first blog post I said "I believe that studying physics is important because it helps us to understand the world around us, it helps one to increase their knowledge and find interest in things they've never even thought to question about, and physics can help me to understand and maybe even improve my athletic abilities." 

The physics of sports has broad applications, and is useful for boosting performance in a variety of athletic disciplines. A lot of the time, good athletic performance is based on proper control and coordination of movement. Other times, it helps to have a good understanding of the physics taking place, and then using this knowledge to your advantage. So my Top Ten will attempt to follow my course of study and understanding through the relationship of track and field and physics. 

1.    Newton’s first law

Newton's first law of motion states that "An object at rest stays at rest and an object in motion stays in motion unless acted upon by an outside force." Objects tend to "keep on doing what they're doing." In fact, it is the natural tendency of objects to resist changes in their state of motion. This tendency to resist changes in their state of motion is described as inertia. Inertia: the resistance an object has to a change in its state of motion.

Sprinters in track are generally seen starting their race using starting blocks. Starting blocks allow a faster and more efficient starting time. While on the starting blocks they are motionless, then they push back on the block and are now in motion. The runner was at rest then the outside force was pushing back on the block then they are in motion. A runner very rarely comes to a complete stop at the end of a race; rather they continue to run through the line in order to slow down. This concept is also the concept of Newton’s first law or inertia which says that an object in motion stays in motion unless acted on by an outside force.

2./ 2.5 Force- Newton’s second law/ Newton’s third law

When a runner is running they apply a force on the ground. With each step a greater force is applied on the ground which the ground applies on the runner thus propelling them forward. According to Newton’s second law the more mass you have the greater the force needed to propel you forward. Force we learned is the action and reaction of pushing and pulling.

Equation:

Force= mass x acceleration

Newton’s third law states that for every action there is an equal and opposite reaction

(Picture of someone on starting blocks)

A sprinter applies a force to the starting blocks which the starting blocks apply to the sprinter thus propelling the sprinter forward.

3.    Speed

In unit 1 we learned that in order to calculate speed we must know the distance traveled and the time it took to travel that distance. Speed is "how fast an object is moving." Speed can be thought of as the rate at which an object covers distance. A fast-moving object has a high speed and covers a relatively large distance in a short amount of time. Contrast this to a slow-moving object that has a low speed; it covers a relatively small amount of distance in the same amount of time. An object with no movement at all has a zero speed.

Speed is the magnitude of velocity. If you are running in a track competition, it is essential that you are faster than your opponent(s). Speed is also an important factor in field competitions like javelin throws along with discus. Speed affects how far an object or a person travels. The same goes for running speed which is measured by the distance traveled and time it took to travel that distance.

constant velocity = distance/time
constant acceleration
      how far: d= 1/2 at^2
      how fast: v=at
for finding the change in velocity one uses the equation a= change in v/ time

4.    Momentum

Momentum=mass x velocity

P=mv

Momentum is a commonly used term in sports. A team that has the momentum is on the move and is going to take some effort to stop them. Momentum is a physics term; that refers to the quantity of motion that an object has. If an object is in motion (on the move) then it has momentum. Momentum can be defined as "mass in motion." All objects have mass; so if an object is moving, then it has momentum - it has its mass in motion. The amount of momentum that an object has is dependent upon two variables: how much stuff is moving and how fast the stuff is moving. Momentum depends upon the variables mass and velocity. In terms of an equation, the momentum of an object is equal to the mass of the object times the velocity of the object. Momentum = mass * velocity. 

The greater the momentum the greater force needed to stop an object. In discus the athlete spins to gain momentum which when the discus is thrown force is applied which propels the discus forward. 

As a long jumper one must run a long lane and then jump by running they gain speed and then exert a force on the ground to propel them farther forward into the pit.

 

5.    Acceleration

Acceleration is the rate of change in the speed of an object.

Acceleration= final speed-initial speed/ time

Acceleration is a vector quantity that is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity. Acceleration has to do with changing how fast an object is moving. If an object is not changing its velocity, then the object is not accelerating. Velocity is a vector quantity that refers to "the rate at which an object changes its position." If a person in motion wishes to maximize their velocity, then that person must make every effort to maximize the amount that they are displaced from their original position. Every step must go into moving that person further from where he or she started. 

I feel like in terms of track this seems pretty self-explanatory.

6.    Potential Energy/ Kinetic Energy

A runner builds up potential energy when they are in the starting blocks. They build up this energy because they are motionless and they have the potential to move. This energy has the potential to be turned into another energy called kinetic energy. Kinetic energy is the energy an object or in this case runner has while in motion.

7.    Work

Machines help us use our energy more efficiently by reducing the amount of force needed to move an object. In this unit, we addressed simple machines. An example of a simple machine is an inclined plane.

Work = F x d.

The inclined plane, and all other simple machines, increase the distance an object moves, in turn decreasing the force needed to move it. Although the force exerted is decreases, the work will remain the same as it would have been lifting an object over a short distance. 

8.    Electromagnetic induction

You’re probably wondering what electromagnetic induction has to do with track and field or sports in general. I’d like you to know that food has everything to do with sports. In order to purchase this food we generally use credit cards. The food we consume before and after these games are as much a part of the athletic experiences as the athletic experience itself.

Electromagnetic induction is the physics behind how a credit card machine works. A big question this year was how does a credit card machine work? A credit card has a magnetic strip. This magnetic strip is a code. When the card goes into the reader voltage/current is induced due to the coils of wire which when reacting to the credit card change the magnetic field. The computer interprets the electric signals back and forth which ultimately read the card.

! Disclaimer the next one doesn’t really pertain to track and field but it was probably one of my favorite things to learn.

9.    Torque

Torque is created when the line of action of a force does not pass through the center of rotation. Torque is what causes rotation. The lever arm is the perpendicular distance between the line of action of the force and the center of rotation. The torque (τ) created by a force is equal to the lever arm (r) times the magnitude of the force (F). There are three ways to increase torque: 

1.) Increase the force, 2.) Increase the lever arm or 3.) Increase both the lever arm and the force.

Along with the torque, we learned why football players are less likely to be pushed over when they keep their legs shoulder width apart versus their feet being together. This is because when the football players have their feet shoulder width apart; they have a larger base of support, which makes it harder to get the center of gravity from underneath them. When the center of gravity is removed from underneath an object or the player, a lever arm is created which also creates torque and is the reason why the object or person will topple over. The center of gravity is where the average amount of mass is being pulled down on by gravity within an object.

10. Tides

Again this one may seem unrelated to track and field. However, I beg to differ. With their bodies in perfect “summer bod” condition trackletes like to enjoy the sun as well on beaches. The physics of tides are:

We learned that to calculate the force between the sun and the earth and the earth to the moon we had the use the equation F= G(m1m2)/d2, and then we plugged in. We learned that the greater force is between the earth and the sun and confused many of us including myself on how tides are caused. Tides are caused due to the location of the Earth. They are caused by the difference in force which is greater than the sun to the earth. They are caused by the difference in force felt by opposite sides of the Earth. We also learned that distance has a greater effect on the force than a change in mass and that everything with mass attracts everything with mass, and everything with mass has a force. This also relates to your weight on earth, so the closer you are to the center the smaller you are and the farther away you are the more you weigh. There are two types of tides; they are spring tides and neap tides. Spring tides are higher high tides and lower low tides. Spring tides occur when the sun and the moon are aligned. Neap tides are high low tides and the lower tides are higher. Neap tides are when the moon is perpendicular to the Sun and half-moons. 

I couldn’t pass this one up. One of my favorite things I learned this year is completely unrelated to sports.

One of my favorite movies as a child was Brother Bear. A huge part of this reason is that there is a scene that shows the Northern Lights.

During the magnetism unit we learned about the poles of the Earth both geographical and magnetically. We learned that the poles that we know are just geographical while the magnetic poles are actually the exact opposite of these.

The northern lights are actually just cosmic particles being pulled to the poles because of the earth's magnetic field. Because the particles are only entering our sight in two places in the world, the concentration is very high. This is why they are visible. Although the Northern Lights may be harmful I have always wanted to visit them, and still do.