Blog 7

In this last chapter, we learned about centripetal force.  I experienced centripetal force while riding on a rollercoaster in California Adventure park.  On the ride, California Screaming, there is a loop.  As the rollercoaster enters it, one experiences what feels like a change in weight at different points.  This is due to the centripetal force.  At the top of the loop, the centripetal force (force pulling towards the center) is equal your normal force+your weight (massXgravity).  However, at the bottom, one's centripetal force is equal your normal force-weight.  This is why, when riding a rollercoaster, you feel heavier at the top of a loop than at the bottom.  With a greater centripetal force, you feel as if you are heavier.  I always wondered why I felt much heavier at the top of a loop than at the bottom.  Now, thanks to physics, I can understand that centripetal force plays a major role in how heavy one feels on a roller coaster.

Blog 6

This week, as we learned about momentum and impulse, I realized that I could take the topic and relate it to baseball.  Using the equation m1v1+m2v2=m1v1f+m2v2f, I found that I could find the final velocity of both the ball and a player after being beaned.  This equation is proved to be true because of the conservation of momentum.  Since a player being hit by a ball is a bouncy equation, the equation above is valid.  However, this equation is not elastic.  The main factor in the equation is the difference between the mass of the player and the mass of the ball.  Due to the extremely large difference, the player sees a very small change in velocity.  And, since the player is at rest to begin with, the only factor in the first part of the equation is the mv of the ball.  This is a very small number, due to the mass.  Since it is a small number, the velocity change felt by the player is also very small.  The ball also experiences a decrese in velocity, due to its losing of some momentum. 

Blog 5

During this week's lessons on work and power, I realized that I could relate the subject to my favorite sport, baseball.  When running down the base line, which is 90 feet, or 27.43 meters, I do work.  This work can be calculated with the equation, W=(Force)(distance traveled).  If I were to run powered by a net force of 10 newtons, my amount of work would be 274.3 Joules.  I can also use this work to find the amount of power that I produce.  Power can be found using the equation Work/Time.  If I were to run to first base in the average time, 4.4 sec, my Power would be 62.34 Watts.  This seems to be a very small power, which may be due to the fact that the force I used above is very small.  With my mass at around 80kg, a force of 10N would mean that I had an acceleration under .125m/s.  I was amazed to find the ideas of Power and Work in baseball.   

Optional Blog

Early this morning, I saw something that directly relates to what we learned in Physics this last week.  I had decided to run an experiment envolving my History book and a stair climbing machine.  When I placed the book on top of one of the machine's legs, the book did not slide down.  I realized that this was because, as we learned in class, the object's axis has rotated.  This means that the static friction will be equal to (while the object is not in motion) the x value of the weight.  This makes the net force in the x plane equal to zero.  A net force of zero means that the object is not in motion.  In the y plane, we learned that the books normal force is now less.  This is because for a net force of zero, the y value of the weight must be equal to the normal force of the book    This means that the normal force will be less because the y value of the weight is always less than the overall weight.  I was amazed that I could use things that I learned in physics when it came to everyday household items.  I LOVE FRICTION

Blog 3

This is a video of the tablecloth trick, which I was able to do on a boring Saturday morning.  I set up my experiment using some of my parent's dishes and my sister's pink blanket.  I was able to pull my sister's blanket out from under a plate and saucer with coffee cup.  This is because of Newton's first law.  Newton's first law states that any object in motion will remain in motion unless acted upon by a net force and vice versa.  This is also known as inertia.  When I began my experiment, the inertia of the plate and saucer allow the tablecloth to be pulled from under it without taking the two objects with it.  Because both objects are at rest, they have a tendency to remain at rest because they do not have a net force.  I thought that it was really cool that we can apply what we learned in physics to different tricks we see in real life.  Now, I know the true causes of the tablecloth trick.   

Blog 2

This weekend, I watched the Notre Dame, Michigan State football game.  With the game tied and 4 minutes left, Michigan State punted the ball.  As Aaron Bates punted the ball in the air, I realized that what I learned this week in physics could be used to graph the flight of the ball.  If we were to use a position graph for beginning of the punt, we could tell both the velocity and angle of the balls flight.  Using these two numbers, we could find out the Vx and Vy through the formulas: Vx=Vcos(theta)  and Vy= Vsin(theta).  I also know that the entire time the ball is in flight, the Vx remains the same.  However, the Vy is continuously changing and when it reaches the ball's peak of travel, it is 0.  I had no idea that vectors and projectile motion played such a large role in the game of football and especially special teams.   This game was great and went all the way into overtime. 

Baseball and Physics

Even though I have played baseball for 12 years, I never understood how large of an impact physics had on the game.  As a catcher, there are many times when I need to catch a foul tip far behind the home plate.  When a batter hits a foul ball, the ball rises from his bat and is put into "free fall".  During this time, the only factor affecting the ball is gravity.  The ball has an acceleration of -9.8 m/ second^2 as it rises in the air (as well as a positive velocity).  When it reaches its peak of flight, the ball begins to move back towards earth at an acceleration of -9.8 m/second^2.  As it moves back towards the ground, the ball's velocity becomes negative.  This entire process may take no more than a few seconds.  This means that, as the catcher, I'm given little time to find the ball and move in to position under it before it hits the ground.  I now know that physics has much to deal with the game of baseball.