# michaelford3

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14

1. ## Star Wars and Physics

It's been quite a while since I've seen a Star Wars movie, but I still remember the necessities from all the movies. It doesn't take a physics prodigy to understand that there are many physically-impossible aspects of the series, but its good to use the imagination every once in a while and ignore these impracticalities. Nonetheless, I can use my knowledge of physics thus far to analyze certain parts of the series. First of all, when the tie-fighters and x-wings explode in the movies, they make a tremendous amount of noise. However, knowing that sound cannot travel through a vacuum (in space) we know that the explosions would be silent. George Lucas, being a smart man, probably already knew this, but nobody wants to watch space ships silently explode. Furthermore, the concept of hyperspace is introduced in the fourth film. Through breakthrough special effects, the audience is encouraged to believe that the characters travel enormous distances in matter of seconds. Knowing that the speed of light, the fastest thing in the universe, (more so than the Millennium Falcon), is only 3.00 x 10^8 m/s, it seems highly unlikely that the characters could transport so fast.
2. ## 10 things I need to know to pass the waves exam

1.)narrow opening + long wavelength = greatest diffraction effects 2.)electromagnetic waves to not require a medium to travel through 3.)frequency is directly proportional to energy 4.)T=1/f 5.)when a wave enters a new material the speed and wavelength can change; the frequency cannot 6.)all electromagnetic waves have a speed of 3 x 10^8 m/s 7.)n=c/v 8.)sound is a mechanical and longitudinal wave 9.)waves that have the same frequency and amplitude traveling in opposite directions create a standing wave 10.)period is the reciprocal of frequency - describes how long it takes for a single wave to pass a given point
3. ## Surfing and Physics

As a native Rochestarian I've never really gotten into surfing. Maybe when I'm older and rich and have my own private tropical island. Even the most talented surfers can't do much without waves though. This relates to the wave unit we are currently studying in Regents Physics. Oceanic waves are transverse waves, because the displacement of the medium of said waves is perpendicular to the direction of propagation of the waves. Where the foamy-top of the waves in the ocean are is referred to as the "crest". This is the same as transverse waves on a 2D graph; the top of the wave is referred to as the crest, and where it dips down is referred to as the trough. Because timing is an important aspect of surfing (I can infer), it means that a larger amplitude for oceanic waves is preferred by surfers. This gives them more time to ride the actual wave. On a two-dimensional graph, the amplitude is measured from the point zero on the graph to either the crest or the trough - many individuals make the mistake of measuring the distance from the crest and the trough to get the amplitude. No math in this post.
4. ## Bats and Physics

Bats are yet another example of a species of animal that I am completely fascinated by. Without bats, mosquitoes and the diseases they carry with them would overpopulate the earth. Bats have terrible vision, yet are capable of feasting on mosquitoes even during pitch black nights. How is this possible? Bats are one of the few animals known to man that are capable of a sophisticated technique called "echolocation". The process for echolocation is simple; The bat sends out a sound wave and waits for the sound to hit an object. When the sound wave hits, it bounces off the object and returns to the bat as an echo. Bats can identify the object by its echo alone; this includes the size, shape and texture of the insects near the bat. Now, using our knowledge of physics, we can create a wave-practice problem using this awesome information about bats. A Noctule Bat's sound wave has a frequency of 20000 Hz, which is surprisingly one of the lowest frequency levels among bats. If it finds a juicy mosquito approximately 2 meters away, we can determine the velocity of the bat's sound wave. The velocity of a wave is equal to its frequency times its wavelength. So if multiply the Noctule bat's frequency times the 4 meter wavelength, (twice the distance away from the mosquito), we get a total velocity of 80000 m/s, or 80 km/s. Don't mess with bats.
5. ## Electric Eels and Physics

My favorite TV show is Animal Planet's "River Monsters with Jeremy Wade." Some BA British guy tackles giant fish. In a recent episode, he puts on a rubber suit and lassos a giant electric eel in a mud pond somewhere in third-world Latin America. It got me thinking about how awesome electric eels actually are. They have specific organs that allow them to create electricity within their own bodies and they use the discharge to stun prey within 50 feet around them. According to Yahoo Answers, these bad boys are capable of emitting 500 volts with 1 ampere in a single shock! With this information and our knowledge of physics, we can solve for the electrical power of electric eels by multiplying both the current and the voltage to attain a value of 500 watts of power! So, the next time you plan on taking a swim in a mud pond in the middle of a cattle ranch in rural argentina, make sure you brought your finest pair of rubber boots with you.
6. ## Lassos and Physics

Cowboys are awesome. Not the Dallas Cowboys, they suck. Part of the reason they are so awesome is because of their lasso, and their ability to wield it. I may know how to tip cows, but being able to throw ropes around their heads and round them up is ten times cooler. This action of spinning said lasso can be applied to physics in that a physics student such as myself can use their knowledge to find the centripetal force and centripetal acceleration of the action. The centripetal acceleration of an object is found by taking the velocity of the object, squaring it, and then dividing that value by the radius of the circle. In other terms, ac=(v^2)/r. If the velocity of the lasso was 10 m/s, and the radius of the lasso was .25M, then the centripetal acceleration of the lasso would be 400 m/s^2. Then, to find the centripetal force, one must take the value of the centripetal acceleration, and multiply it by the total mass of the object. So if the mass of the object was .1kg, then the centripetal force of the lasso would be 40N. Sorry Dallas Cowboys fans. Better luck next year.
7. ## Driving and Physics Part II

In addition to momentum and impulse, the unit of kinetic equations can be applied to driving. Again, we will use my mom's old Nissan Ultima as a demonstration. We recorded that the car's initial velocity was .01 m/s. Let's say that after negatively accelerating (NOT decelerating) at a rate of -2 m/s^2, the velocity became .005 m/s. If, for whatever reason, we wanted to find the time in which all this happened, we would use the kinetic equation, Vf=Vi +at. To make this easier to solve, we would use our knowledge of algebra to convert the equation to t= (Vf-Vi)/a. After plugging in all the known variables, with units, we would solve to see that this shindig went down in .0025 seconds. The idea that a car is capable of changing speed faster than a human blinks an eye is rather strange, but then again you've never seen me drive.
8. ## Driving and Physics

I am a bad driver. Perhaps reviewing the physics of driving will somehow make me a better driver. There's probably some sort of correlation between driving a car and all the other units that I've learned in physics, but the only unit I can think of right now would be the momentum and impulse unit, coincidentally one of my least favorite units. First of all, momentum is the equivalent of an object's mass times its velocity. So, if I wanted to find the momentum of my Mom's Nissan Ultima on a snowy day, I would take velocity of the car, .01 m/s, times its mass, 3000 kg, to get a momentum of 30 kg x m/s. Next, the impulse of an object is measured in several ways, including finding the change in momentum. If the momentum of my mom's car shifts to 20 kg x m/s, then that means to find the impulse of the situation, all I would have to do is subtract the two values, to get an impulse measurement of 10 Nxs.
9. ## Cow Tipping and Physics

After the work and power unit has come to a close, it really got me thinking about how such topics would apply to the art of cow tipping, a guilty pleasure of mine. (Not really - I unfortunately do not live near any tippable cows that I know of). Work is the measure of force times displacement on an object. Let's assume the cow of my choice for tipping weighs 3000N. If I were to not only tip over but also push the cow on the ground, specifically a distance of 1 meter, then that would mean that I exerted 3000 joules of work on the cow. Not a bad workout. Now, after pushing this cow on the ground, I felt pretty powerful. But how powerful exactly was I? Well, let's say that I completed this entire task in 30 seconds. (I had to work diligently to avoid getting caught by Farmer Brown). 3000 joules divided by 30 seconds is equivalent to a value of 100 watts. So, the next time you and your friends are sneaking around a farm tipping cows, remember to measure the force of the cows, how far you push them, and how long the process takes, so you can find out how much work you exerted, and how powerful you were.
10. ## Spiders and Physics

Spiders scare me. It is a fact that I am ashamed of, but nonetheless it is true. I've been told that one of the ways to eraticate a specific fear is to develop a stronger understanding of it. However, there are many incredible facts about spiders that I just can't seem to understand. For example, jumping spiders can jump distances over 50x their own length. This fascinates me, because it would be the equivelant of me, barely 6 feet tall, doing a standing broad jump that scales over 300 feet! The world record for a standing broad jump for a human was set in 1904 by Ray Ewry, who jumped a distance of 11.4 feet. This makes me wonder exactly how the jumping spiders are internally structured to be able to be capable of doing such a thing. In addition, some spiders are also fast on their feet. The common wolf spider (which is native to Rochester) can travel at about 2 feet per second. I find it astounding how it is even posssible for a bug to be able to move that fast. Hopefully, as my understanding of physics grows, I will be able to calculate how fast wolf spiders will be able to move if they were much larger. I'm not sure if understanding spiders more will truly make me less afraid of them, or if it will just make me even more horrified of them. Either way, they are very cool to learn about.