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leiser24

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About leiser24

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    Junior Member
  • Birthday 11/22/1996

core_pfieldgroups_99

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    Irondequoit, New York
  1. Everyone knows that one of their favorite past times is sitting in front of the television and watching movies, shows, or playing video games. However with this almost motionless, lazy activity comes a great deal of static physics and mechanics. When you are sitting down enjoying whatever show it is you may be watching, you actually have several forces acting on you concurrently. For example, by sitting on the couch with no extra weight on you, your weight is equivalent to the normal force, or the force of the couch on you. In addition to the force of the couch of you, if you are leaning on an arm or laying down, a similar force acts on you, except at an angle or incline. The general rule for laying on the couch watching television is that whatever force you exert on an object, that object exerts the same force in the opposite direction, or 180 degrees around. Next time you sit down and watch some television, remember that you are under the rules of static physics!
  2. Everyone knows that one of their favorite past times is sitting in front of the television and watching movies, shows, or playing video games. However with this almost motionless, lazy activity comes a great deal of static physics and mechanics. When you are sitting down enjoying whatever show it is you may be watching, you actually have several forces acting on you concurrently. For example, by sitting on the couch with no extra weight on you, your weight is equivalent to the normal force, or the force of the couch on you. In addition to the force of the couch of you, if you are leaning on an arm or laying down, a similar force acts on you, except at an angle or incline. The general rule for laying on the couch watching television is that whatever force you exert on an object, that object exerts the same force in the opposite direction, or 180 degrees around. Next time you sit down and watch some television, remember that you are under the rules of static physics!
  3. For those who follow or play lacrosse, hockey, and even soccer know of bar down goals. A bar down goal is one of the coolest goals a person in one of these sports can score, it's where the ball hits the crossbar on the shot and goes straight down or back into the net. It can get a team hyped up in a matter of seconds, but how does it happen? To start, why doesn't the goal come flying up with a powerful enough shot? Well, knowing the laws of momentum and motion, a lacrosse ball, or hockey puck, hitting the crossbar of an iron goal at 80 miles per hour won't move the goal much, as much momentum as the object may have. The equation p=mv proves that a lacrosse ball or hockey puck 1/100th the mass of a lacrosse or hockey goal won't do much damage and move the goals, and is the primary reason a bar down shot looks so good. The ball accelerates downward off of the crossbar at 9.81 m/s^2, and since the weight of the goal is so great in comparison to the puck or ball, the crossbar actually provides a force for the rubber ball or puck to accelerate off of. Next time you watch a lacrosse or hockey game and see a bar down goal, remember the physics of it that makes it so cool.
  4. Awesome! Wile E is the best!
  5. The other day I came across an idea that seemed unreal, a tourist attraction only for the elite members of society, an elevator into space. The concept is actually quite simple, and would make tourism into space much cheaper and easier. The idea uses a counterweight, or station, in space with a suspended cable anchored to a mobile point on earth's surface. Gravity would be pulling the cart down, as the coriolis effect, or force, pushes the cart horizontally, tilting the cable, as shown in the diagram below: Some of the math explaining the gravitational forces is more complex though, however. An upward centrifugial force acts against earth's gravitational pull downward, dependent on the height of the object. The apparent gravitational field can be represented this way: The downward force of actual gravity decreases with height: The upward centrifugial force due to the planet's rotation increases with height: Together, the apparent gravitational field is the sum of the two: where g is the acceleration of actual gravity or apparent gravity down (negative) or up (positive) along the vertical cable (m s−2), a is the centrifugal acceleration up (positive) along the vertical cable (m s−2), G is the gravitational constant (m3 s−2 kg−1) M is the mass of the Earth (kg) r is the distance from that point to Earth's center (m), ω is Earth's rotation speed (radian/s). (From Wikipedia given sources). Building an elevator into space would take unprecidented manpower and spending, however a completed project would begin a new era in human exploration and tourism, opening a previously unknown to civilian frontier.
  6. Something that is on most people's list of things to do before they die is skydiving. The thrill and passion of overcoming a common fear of heights drives thousands every year to jump out of an airplane five thousand feet in the air. But do you know how much force you exert free falling towards the earth? Let's say you jumped out of a plane five thousand feet in the air, neglecting air resistance, what would be your force in newtons? Well, according to the equation F=ma, and knowing that a= 9.81 m/s^2, and your mass in kilograms is 60, your force would be close to 600 N! After you jump from the plane, you realize that you forgot your parachute (which would not be good), how much time do you have before you hit the ground (and survive of course)? Well, by rearranging the formula d = vit + (.5)at^2 to solve for time, you know that you have 311 seconds before striking the ground, plenty of time to solve for t and pray. So when you fulfill your bucket list and finally skydive, remember the simple mathematics of your free-fall.
  7. Neon lights are very common on signs for business that stay open late, and everyone has seen the recognizable "open" or "closed" sign during their late night runs to Taco Bell. These lights are very simple in how they work, and use less energy than traditional light bulbs. Most neon light tubes are filled with gases such as argon and neon, which are lighted when the atoms of the gas emit photons. This happens when electricity is sent through the tube, exciting the electrons in the gas, making them jump up to a higher energy level, and when they drop back down they release photons in the form of light that we can see. Neon lamps and lights are very simple, and if you would like to know more about them and in greater detail, view the video posted in the link below. http://youtu.be/zPDoBjlpxXY
  8. leiser24

    Lacrosse

    Cool post, glad to know the physics of lacrosse now
  9. Have you ever been doing chores or showering and wondered how the water comes out of the shower head or faucet? Well, if you have, this blog entry will explain the basics of how they work. A faucet is a device that regulates the flow of water in a system, such as a house or school, and without them, water would be flowing constantly out of pipes be almost useless in everyday life. SImple machines work to control the pressure and flow of water, including levers and screws. The pressure inside of water pipes is much higher than the pressure of the air outside of the tube, which allows the water to flow up from the ground, against the force of gravity, and out into the kitchen sink. However, in the way, are small openings and valves, such as check valves, which do not allow the flow of water back past the valve. This keeps the water flowing at a normal pace, only to be blocked by more valves, like the ones in faucets, which must be manually turned to allow the flow of water, from hot and cold pipes. Next time you use your shower or wash the dishes, remember the physics and engineering principles of the flow of water, and how all that work is done just to clean your hair or a glass from lunch.
  10. A lacrosse ball is a solid sphere composed of a hard synthetic rubber material, which allows it to be heavy enough to throw with maximum speed and momentum, yet flexible enough to bounce. There are many aspects of the ball that are related to physics. For instance, the "grippiness" of the ball gives it the ability to spin when thrown out of a player's stick, creating centripital force, and if the ball gets spinning fast enough, let's say on a really hard shot or long pass, the ball can actually vere off normal trajectory lines and "curve". This phenomenon is very similar to a pitcher on a baseball field. When the ball hits the turf or crossbar, it can bounce a great distance depending on the initial velocity of impact with the surface.
  11. Nowadays basically every teenage male and female carries a device capable of playing music portably, through small speakers or large, over ear headphones. Many companies now offer "noise-cancelling" devices, that divert any sounds from outside the headphones while they are playing, rather than the smaller, in-ear speakers that produce smaller amounts of bass and volume. Have you ever wondered how your earpod works? In-ear headphones are small speakers that direct most of the sound waves into the ear canal, while the over-ear headphones create more movement and vibration, which translates into more bass and louder sound, over a larger area. The electronic signals from the mp3 file travel through the wires and are converted into sound energy with a small magnet in the speaker. These speakers will vary in size and strength depending on the quality of the magnet and the components that are attached to the magnet, like the diaphrahm, or cone. Most of the time these speakers are put into "boxes", that amplify the sound in a certain direction or magnitude, which is how the size or shape of the headphones come to be. Size does not necessarily matter in the case of headphones either. Companies will promote their headphones as "bigger" and "better" than the next, which is not always the case. When purchasing your next set of over or in-ear headphones, remember to try them out and read reviews before purchasing, or build your own! Building speakers is a simple project, and requires little to no money invested. Below is a simple diagram of how a speaker works:
  12. leiser24

    The effects of G-Force

    Cool video and very interesting post!

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