  t_hess10

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1. There are many examples of waves in our daily lives, such as water waves, earthquakes, and radiation. Although these might be different types of waves, they all have one thing in common- they all have wave speed. You can determine wave speed with the equation, s=f(lambda). S represents the wave speed, f represents the frequency, and lambda represents the wave length. As an example, if you were looking at a side view of water waves on a beach and the distance between to wave crests was 10 meters, and .5 waves pass every second, your able to solve for wave speed. By using the equation given, multiply (10m)(.5Hz), which will equal a wave speed of 5m/s. Overall, wave speed is very simple to solve for when you know the wavelength and frequency of a wave.
2. In the study of waves, there's many different types of waves. First, there are mechanical waves, such as sound, water, and seismic waves, which all require a medium to travel through. In contrast, there are electromagnetic waves, such as visible light and x-rays, which all don't require a medium. Also, when looking at waves, the crest is the top, such as the top of a wave on a beach, and the bottom is called a trough. The length between two crests is known as a wavelength and the amplitude is the distance from a medium to the crest, or to the trough. Also, waves have a frequency, which the number of waves in one second, and the period, which is the time of one wave.
3. When knowing the way magnets act with each other when in close proximity, you can determine many ways other objects act around them. First, if a magnet runs north to south with the north side of the magnet on the left side of a picture and a compass above the magnet, your able to determine the direction of the compass. Since compass's point in the direction of the magnet field line and the magnets' magnetic field lines run from north to south, the compass would be pointing to the right, since it was above the magnet. Also, a magnetic field strength is greatest when in the most dense area of magnetic field lines. Lastly, the greatest strength of an electromagnet is if it's wrapped in iron. Overall, there's many problems you can solve with magnets, knowing how they act alone and around other magnets.
4. In magnets, there are many rules to need to know. First magnets run from north to south outside the magnet and south to north inside the magnet. Also, magnetic field lines show the flow of these electrons and how they interact with other magnets around. When two magnets are close to each other with both of their closest sides the same, the magnets repel each other and magnet field lines shown in between the magnets are seen repelling away from each other. Also, when two magnets are close to each other with their closest sides being opposite, they attract, which is shown with magnetic field lines. Overall, by using these need to knows, you can determine many question with magnets.
5. VIRP tables are the best use to find missing information in either series circuits or parallel circuits. However, there's different rules for each type of circuit. First, in a series circuit, all the currents are the same for the total and each resistor. However, the voltage is the same for all resistors and the total in parallel circuits. Also, in a parallel circuit, to solve for the resistance, the addition of 1/each resistor equals 1/total resistance. Lastly, to find missing information, you can use both R=V/I and P=IV. Overall, when using the VIRP table, you can solve any resistor circuit problem given.
6. Although I described the importance of Newton's laws in retrospect to baseball, I have learned many more connections between physics and the exciting sport. One example would be the momentum of a baseball after being released by a pitcher. If Tanaka of the New York Yankees, with a .145kg baseball, threw a 42 m/s fastball towards home plate. You could find the momentum of the baseball by using the equation, P=mv. When plugging in the numbers P= (.145kg)(42m/s), you get momentum to equal 6.09 N*m/s. Furthermore, you can also see the power and the work of Gardner running down first base after making contact with a baseball. Gardner runs down to first base with a force of 800N, which is 27.432m long, at in 2.2 seconds. You can determine his work produced first by using the equation W=Fd. When plugging in the numbers, W=(800N)(27.432m), you find that Gardner produced 21,945.6J of work. Also you can find his power produced by using the equation, P=W/t. After plugging in the numbers, P=(21,945J)/(2.2s), you find that Gardner produced 9,975.27W of power. Overall, I has seen even more connections between baseball and physics in the last couple months, and I hope to find more.
7. Although you don't see many examples of springs throughout our daily lives, one big example is the springs for our cars. You can determine the potential energy of a spring by using the equation PEs = (1/2)kx^2. For example, if a car has a spring constant of 30,000N/m and the spring compresses .1m after landing on the ground, you can determine it's potential energy by multiplying. So, (1/2)(30,000N/m)(.1m)^2 = 150J.
8. When watching a 100m dash, I've never thought about the work and power that was used by the runner until now. If the runner exerted 500N of force over the course of the 12 second run, then you can determine the runners work and power. For solving for work, W = Fd. So, (500N)(100m) = 50,000N*m of work done. Then, to solve the power that was used, P = W/t. So, (50,000N*m)/(12s) = about 4,167 Watts of power used.
9. I've realized that when looking at a collision, the momentum remains the same in it; however, what we see is the change in velocity. An example would be a 2kg Velcro ball traveling 30m/s that made contact with a 10kg Velcro block initially at rest. When the collision occurred, they stuck together and traveled 5m/s. If you were to look at the momentum before and after the collision, the momentum is the same. Therefore, no matter the type of collision, although the velocity in a collision may vary, the momentum remains the same.
10. By learning about momentum and impulse, I can now see how it relates to car crashes. If a 1000kg car was going 10m/s, and then a 5000kg truck hit it from behind with a force of 2000N for .5 seconds. You can find the car's change in momentum, or impulse by using the equation J=(m)(change in v). First though, you have to find the final velocity of the cart using F=m(change in v). When plugging in: 2000N=(1000kg)(change in v), velocity equals 2m/s. Then plugging in using the first equation: J=(5000kg)(2m/s), then the impulse would equal 10000kg*m/s.
11. After learning about Newton's 3rd Law, I thought about tug of war. I now know that when someone on one side of the rope is pulling on the rope, the force the person is applying to the rope and the force the rope is applying to the person are equal, no matter how hard the person is pulling. However, although the magnitude of the forces are equal, the direction of them are opposite, since the person is pulling the rope towards him/her and the rope is pulling away from the person.

Also, I look can look at the net force between someone pulling on the rope with 200N and another person on the opposite end pulling with 100N. The net force of these two forces would be 100N towards the person pulling with a force of 200N. Lastly, due to the solution of the net force, this shows that the forces aren't at equilibrium because the net force isn't at zero.
12. One of the sports I like to do during the winter is skiing. When referring to physics, I can think about a lot of relationships comparing both. When skiing down an declined mountain, I know that mg or the weight of gravity is acting on me, as well as the the normal force of the mountain pushing up on me in a perpendicular direction to the mountain. Also, there's a force of friction pushing back me, but not much since I'm accelerating down the mountain. Overall, there's many examples of how newton's laws and/or physics applies to skiing.
13. Other than baseball, my second favorite sport is football. While watching it or playing, you can notice a lot of physics incorporated into the sport. On of the major examples I can think of is it's relation to angled projectile motion. If you were to say the Giants had one more play to score the game winning touchdown and the quarterback needed to throw a 40 meter touchdown pass, infering that he throws the ball at an angle of 45 degrees. But, threw the ball with an initial velocity of 22 meters per second and the pass was caught at the same height it was thrown in 3 seconds. You then can determine if the pass made it pass was made it 40 meters or not. To solve this you would first use V(x)=Acos(theta). After plugging in the numbers you get 15.56 meters per second. After, you use the equation d=v(initial)t + (1/2)at^2. The (1/2)at^2 cancels out becuase a is 0 meters per second squared, and after you plug in the data you have, you get the distance to be 46.68 meter. Therefore, the pass made it passed 40 meters for a touchdown. Overall, this is the best example I can think of when I think of physics and football.
14. Throughout my life, one of my greatest interests has been baseball. I've been playing it since I was 4 years old and now, I even play it during every season of the year. As I've gained more knowledge about physics, I've been able to connect physics more to baseball. One thing I can apply, is that when a ball it traveling from the moment it leaves contact with the bat, to when it is caught by the outfielder, a v-t graph would have a line starting very positive and then decreasing at a constant velocity until it stops negatively on the graph below zero, since the ball falling would be the negative direction. Also, if you were to look at the displacement of a pitcher pitching the ball to the batter and the batter hitting the ball right back to the pitcher, in which he catcher it, the displacement would be 0 because the ball ended back where it had started. Furthermore, I'm taking physics because I hope to go into the field of engineering due to interest of math and science, compared to all other subjects in school. What I'm most excited about this year is doing the hands-on labs because I can't stand lectures. Also, what I'm most anxious about this year is finding out whether or not I actually have an interest in physics.
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