# kyraminchak12

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## Blog Entries posted by kyraminchak12

Throughout my field hockey season this year, me and several of my team mates had the joy of being at the wrong place at the wrong time when another team mate was hitting the ball. Most recently, during the semi finals, I got hit twice within the same half while blocking up a hit. Let's just say being 5 yards away while someone is driving a ball in your direction isn't always the most safe option. But today in class my teacher brought up Newton's third law, every force has an equal and opposite force. This reminded me of getting hit in the sectional game. The force my teammate applied to the ball that sent it straight into my ankle and then into my knee later in the game, was the same amount of force my leg applied to the ball on contact. The only difference was the direction of the two forces. Unfortunately the ball one that time, and i still have the bruise to show for it!
Ever since i got my permit I've been obsessed with driving everywhere, as lame as that sounds, it's true! Yet i know that i would not be able to drive if it wasn't for physics. One of the issues i have had is the remembering to take off the parking brake. I always forget when i start the car that i have to take brake off before the car will actually go anywhere. Since i always i forget this, the car is stationary (a constant velocity of zero) and the forces acting upon the car are equal, until i apply a force that would allow the car to move. The only two forces acting upon the car are gravity and the normal force of the ground that the car wheels are resting on while stationary. If we were to draw a free body diagram of the car it would look like: a dot (which represents our car) with an arrow coming straight down labeled mg (which represents the force of gravity) and an arrow up labeled Fn (this represents the normal force of the ground pushing up on the car). If the forces of gravity and the normal force were not equal, then the car would either float up into space or be pulled through the ground, so it is very important that since the only forces acting upon the stationary car are in the vertical direction that they are equal, so neither of these occur. So physics and stationary cars actually do have a lot in common! and without physics the car would either be flying or sunk down into the either, which in the ideology of cars, isn't the best option.
So for about 3 months now, i've been working at a small pizzeria in town and it came to my attention recently that at work, i don't really do any work. I may go and get peoples orders from the back, or answer phones, but i never move from my spot at the front counter without returning to it. So since there is no total displacement in my location for the shift that i work, i technically am not doing any work. Sure it takes energy to do the jobs that i have to, like deal with rude people on the phone or struggling to find a button on the computer, but i don't actually do any work while i'm at work.
i don't know one person who actually enjoys walking up the stairs. in fact, i hear people complain about having to climb 3 flights of stairs multiple times a day! yet why is it so miserable? well in order to lift yourself up one step, there needs to be a force of at least your weight in order to go up the step. when there is a large amount of steps, that's a lot of work that is done in order for you to walk up the steps. since work is being done because a force is causing a displacement, that also means that there has been a change in energy. As you get higher up the steps you increase your potential energy. it's true, physics is really anywhere.
about two and a half weeks ago, while everyone was still on the bath craze, I googled how to make my own bath bomb. I was home alone and had way too much time on my hands. so I found that if I put olive oil and cinnamon sticks in my bath that it was very good for my skin. so having nothing better to do with my time, I made the bath. well I forgot to clean out the tub after, and when my sister took a shower, she slipped right on her but. this is because the oil from the bath filled in all of the divits in the shower, so there was little to no friction on the tub's surface. without this friction it makes it very hard to successfully move about while taking a shower and not falling. so next time, i'll just stick to a lush bath bomb
During my junior year of high school, my 5th year playing field hockey, i made several connections with field hockey and physics, whether i wanted to or not. As center mid for my team, i am involved in almost every play, so i see in every way, shape and form how physics dictates the way the game is played. In our sectional game i had a beautiful aerial that went over everyone and straight into the circle where a teammate was and the play lead to a beautiful goal, which helped us with the game! Later i then realized that the aerial that i played was a perfect example of a projectile. Since the ball was only being impacted on by gravity it made it the perfect real life application to physics. The ball when i lifted it flew in a path of a parabolic arc due to the fact that it was sent into the air at an angle. This also means that the ball had the same speed the minute it left my stick to the moment just before it hit the ground. The fact that the ball also became a projectile the minute it left my stick means that the horizontal components and the vertical components are different, and only the time is transferable between the two. For example the acceleration of the vertical component of the ball was 9.81 m/s^2 where as the acceleration for the horizontal component of the ball was 0. This is due to the fact that the ball had no force pulling it horizontally, which meant that the horizontal speed remained constant, however, there was a force acting on the ball vertically, gravity, this then pulled at the ball with an acceleration of 9.81 m/s^2 increasing the velocity of the ball as it fell. Field Hockey is truly filled with physics, and the projectiles are just one small component of the sport.
At practice today, we were preparing for the next upcoming tournament (USA Disney Tournament) which is less than a month away. Our coach has us to a wide range of things at practice today, like she usually does. but there was one drill we spent a specifically long period of time doing. it was quite a simple drill, considering all of the girls there have been playing field hockey for years, but it had everything to do with momentum. Coach Tori had us roll the ball to a partner and we had to run up to the ball, collect it, and then keep moving all in one fluid motion. Although the drill is quite simple, momentum played a part, not only with the ball, but with the player as well. We had to keep our momentum going forward, while stopping the ball to change it's momentum. Coach Tori explained that it would never work right if we were stationary while we stopped the ball, because it would take too long, and be counterproductive if we cut to the ball and then just stood there. this also makes sense because it takes more energy to start moving, rather than to keep moving. We had to keep our momentum going forward instead of stopping then trying to go.
In practice last week, our coach had us working in stations. One of those stations was lifting the ball and trying to hit the wall as high as we could. She had us start really close to the wall and focus on the fundamentals and then once we mastered getting the ball high in the air up close, to back our way up. What i realized when i got home was that we had just learned a bunch about the conservation of energy in objects, and how it is never created or destroyed. As soon as i did work on the ball for it to move, i gave it kinetic energy. As the ball continued to increase in height, that kinetic energy transitioned into gravitational potential energy. Then when it struck the wall a small amount of thermal energy was created, then the ball increased in kinetic energy while falling. Then finally once the ball hit the ground all of the kinetic energy was converted into thermal energy.