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  3. 007 Physics

    Recently I watched the film 007 Casino Royale, the first installment of the James Bond series with the new Bond (Daniel Craig), and while the movie was very good (and equally dense) there were many inconsistencies with the real world, such as the statistical improbability of the cards, but this is a physics blog so I will talk about the physics of a certain action packed chase scene in the beginning. The parkour scene takes us through a construction site. One thing I noticed is that at one point when the man being chased jumps down an elevator shaft, uses the wall to jump back and forth, and I believe that the force of friction between his shoes and the wall would not be great enough to support his jumps. Also, there is a large explosion that happens very close to the villain, and the blast would have most certainly effected him, the momentum of the explosion would be enough to carry him through the air. Lastly, James Bond makes about a 25 ft jump, rolls and then falls another 10 feet onto a metal crate which he crushes. The impulse delivered to bond would have been enough to kill him, or at least knock him out. But he just shakes it off and the chase continues.
  4. Last week
  5. COMPLETE BACHELORS QUICK WITH FAST BACHELORS DEGREE E-learning is now moving to be the future of education. Here is an advice for students from the influencers of the world. They can now complete their bachelors quick with fast bachelors degree and move a step towards career.
  6. Thank God I'm a Clemson fan... Saturday was an awful day for me watching the Raiders fall to the Texans; but Monday was a different story. My Clemson Tigers won the College Football Playoff Championship with a thrilling victory over Alabama. It was one of the most exciting games I have ever watched and was definitely well worth staying up till almost 1 on a Monday night. Although I could talk about the physics of Deshaun Watson holding up the National Championship Trophy, that would be a little too similar to my last embarrassment of a blog post. Instead I want to talk about the rotational velocity of Deshaun Watson during one especially big hit put on him during the game Monday. As I was watching the game and I saw Watson helicopter through the air, my first thought wasn't: "Is he ok???" It was more: "Hey! what a great idea for a blog post!" So here I am, about to calculate the rotational velocity of Deshaun Watson. As you can see by watching the video of the hit below, Deshaun was sent into the air and from hit to re-contact with the turf, his flight took approximately one second. He rotated almost exactly 1.5 times and therefore, using rotational kinematics, we can find that he was rotating at over 9 radians per second. Converted to rpms and that would equal 90 almost exactly. Now most people cant put 90 rpms into context, so here's another way to look at it: Deshaun Watson is 6'3", which means layed straight out, he forms the diameter of a circle that is 75" long. When calculated, the circumference of that circle is 235.7 inches, and knowing that his head and feet traveled 1.5 circumferences, we can calculate that his body parts on the outer edge of the circle whipped around at 19.9 feet per second. Converted to mph, thats 13.4 miles per hour! That may not seem like alot but just imagine sprinting at someone and colliding helmet to helmet at over 13 mph. That wouldn't feel too good! This is exactly what could have happened to Deshaun's head but with the additional force of that other person- running at speeds of up to 20 mph- exerted on his head. Although I know the math is far from perfect, thinking about football through physics like this makes one appreciate how these athletes put themselves on the line for the games they love.
  7. Name: You Can't Run From Momentum! (a momentum introduction) Category: Momentum and Collisions Date Added: 2017-01-12 Submitter: Flipping Physics Two kids walk through the woods discussing momentum. I mean, who wouldn’t? Okay, fine. It’s a basic introduction to the concept of momentum. Want Lecture Notes? This is an AP Physics 1 Topic. Next Video: Force of Impact Equation Derivation http://www.flippingphysics.com/impact-force.html Multilingual? Please help translate Flipping Physics videos! Previous Video: Instantaneous Power Delivered by a Car Engine - Example Problem Please support me on Patreon! Please consider becoming a Flipping Physics Quality Control helper. You Can't Run From Momentum! (a momentum introduction)
  8. Two kids walk through the woods discussing momentum. I mean, who wouldn’t? Okay, fine. It’s a basic introduction to the concept of momentum. Want Lecture Notes? This is an AP Physics 1 Topic. Next Video: Force of Impact Equation Derivation http://www.flippingphysics.com/impact-force.html Multilingual? Please help translate Flipping Physics videos! Previous Video: Instantaneous Power Delivered by a Car Engine - Example Problem Please support me on Patreon! Please consider becoming a Flipping Physics Quality Control helper.
  9. Looks like this needs a little bit more work on the formatting, but it is interesting that these two are very similar to each other.
  10. That does NOT look pleasant...
  11. The kronwall

    Kronwall is one of my favorite defenseman in the NHL. The reason for this being his huge hits that he has (shown below) and this great defensive play. The reason for hit great hits is because he combines his massive self with a good amount of speed to completely wreck players. The main reason this is so effective is because of a fundamental aspect of physics which is the idea that momentum must be conserved. Since he catches his opponent off guard it allows him to build speed and use his mass to collide with the other played and cause for him to continue on in his original direction. Even though his speed gets slowed significantly from this it is because he has just collided with another massive player. But, since he has more speed and a better center of mass this opponent gets "Kronwalled"
  12. Physics of Dunking

    There is plenty of physics when it comes to playing basketball, from shooting a three pointer to dunking. In this blog I will assess the physics behind dunking a basketball. First off, you probably have to be a decent height, the shorter you are, the more force your legs will need to provide. Having a high vertical is the most important thing, however, for example Michael Jordan, one of the greatest dunkers of all time, had a 40 inch (1m) vertical. Now the initial velocity needed to reach this height (with the acceleration due to gravity at 10 m/s) is 4.47 m/s. Assuming the force your legs provide is over a time of .5 seconds, the acceleration is about 9 m/s. Given that Jordan was 100 kg, the normal force provided by the ground (created by his legs) is approximately 900 N! Clearly, there is some strong force required to jump and dunk, which is why you should never skip leg day, but more physics behind leg day another day.
  13. This past week in physics, we learned about Gauss's Law for electricity. It states that the electric flux, or the amount of electric field penetrating a surface, is proportional to the charge enclosed within the surface. Interestingly, Gauss's Law does not only apply to electricity: it also applies to gravity. According to Wikipedia, gravitational flux is a surface integral of the gravitational field over a closed surface. This is analogous to electric flux, equivalent to the surface integral of the electric field over a closed surface. Gauss's Law for gravity is mathematically represented by this equation: {\displaystyle \scriptstyle \partial V} {\displaystyle \mathbf {g} \cdot d\mathbf {A} =-4\pi GM} , where represents a surface integral over a closed surface. Gauss's Law for electric fields states that: = {\displaystyle \scriptstyle _{S}} {\displaystyle \mathbf {E} \cdot \mathrm {d} \mathbf {A} } . Electric flux can also be represented by 4 pi k Q. Since G is the gravitational constant analogous to k for electricity, and since M is analogous to charge, it makes sense that total gravitational flux is equivalent to -4 pi GM. Gravitational flux is negative because gravitation fields always attract, where electric flux can be positive or negative depending on the enclosed charge.
  14. Falling down the stairs

    So last night it was very late and dark and my mom decided to leave a basket at the top of the stairs. I think you can see where this is going from the title. So going down stairs was very fast. And getting up the only thing that I could think about is what just happened in terms of energy. The first thought that I had was how much potential energy I had at the top of the stairs. The next was how much transferred into kinetic energy from falling down the stairs. Then I thought about the mid way point where I had kinetic energy, potential energy and a little rotational energy. I found this funny because physics changes the way you think, you can be sitting on your butt at the bottom of the stairs and still be thinking about how it relates to physics and then realize you have an EM exam on Friday!
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  16. Stomping in the snow

    When you are walking in the snow have you ever noticed that when your foot lands in light, fluffy snow your footprint is actually bigger than it is and you can see the extra space with your foot still there? This happens because when you are bringing your foot down it traps a pocket of air between your foot and the ground. As a result of this once your foot hits the ground that air pocket is dispersed thus it causes for the snow around your foot to move even though you are not touching it. This can be pretty satisfying when you are walking home in the freezing cold with nothing to do.
  17. Wouldn't this also have something to do with frictional force as well. If leaning to one side there would be more normal force increasing the frictional force on the side slowing it down on that one side applying a torque force, spinning the sled.
  18. Sleding

    Many people spend the winter practicing thrilling winter sports such as skiing or snowboarding, but I like to stick with simplicity. Sleding requires very limited skill to still have the thrill of gliding down a hill. There is also a lot of physics behind sleding, specifically how to turn on a sled. People seem to automatically know that they should lean to a side to turn to that side on a sled, but why? It's all about the normal force. The sled glides down the hill because of the force of gravity on the sled and the person in the sled but turning is a different story. Once a person leans to the side they are push by the snow because they have rotated the snows normal force on the sled. Initially the normal force is perpendicular to the sled but once the sled is turned, the normal force is at an angle, causing the sled and the person to be pushed to the side. This is why simply leaning to the slide one wants to turn works in sleding, and the basic concept even holds true in skiing and snowboarding.
  19. It's a lot of fun to stick the balloon to a cat or dog and see them react to a strange object.
  20. I have always liked ping pong, but if you are good you could hit it back even harder and surprise your opponent...
  21. Autonomous Landing

    Anybody even slightly interested in science and technology will have heard of a relatively new space company called Space-X. They are very close to launching yet another craft into space set currently for Jan 14th. But, one of their most memorable accomplishments, for me at least, is when they had a Falcon 9 rocket land on an autonomous barge that was floating in the Atlantic Ocean. The physics and calculations that had to be done before hand, and during, had to be crazy. The team at Space-X would have had to write programs for the rocket and the ship to be able to talk to each other, they had to have very precise GPS to put the rocket in the same place as the ship. Other things they had to account for is that the ocean is wavy and the barge would be moving all over the place, they had to make the barge be very stable and still, making it move to directly under the rocket. To make sure that the rocket didn't have too much speed as it touched down on the barge they had to program for a very precise 'suicide burn' that would stop any lateral movement and greatly reduce the vertical movement. All of these physics calculations came into a very amazing and groundbreaking landing. Hopefully Space-X will continue to do new and exciting things to make space travel cheaper and safer.
  22. This past week in Physics C, we started the electricity and magnetism course. It has proven to be very difficult so far, especially when talking about electric fields and finding electric fields at a point by integrating across an object where its charge is uniformly distributed. I am even more scared to start learning about Gauss' Law. Since I do not entirely understand the hard stuff yet, I'll talk about simple electrostatics which can be seen in everyday circumstances. Charging by conduction, for example, occurs when materials become electrically charged by contact. This can be seen by rubbing a balloon against your hair. The atoms in your hair lose their valence electrons, which are transferred to the balloon, leaving your hair positively charged and the balloon negatively charged. If you place the charged balloon to the wall, it will stick because the wall is more positively charged than the balloon, and since opposite charges attract, the balloon sticks to the wall.
  23. Yeah Paul is garbage man, you should get a better team mate. I can't remember the last time that David and I lost
  24. I wonder how elastic the collision between a ping pong ball and a ping pong paddle is. Some of the energy must be converted to sound energy, and some energy must be lost due to friction.
  25. I wonder how much of the original potential energy when the roller coaster is at its highest point is lost due to friction. Also, doesn't air resistance do work on the roller coaster, changing its energy as a system?
  26. Yeah exactly, as a fellow tennis player, its cool to think about physics behind it. Tennis is a game full of conservation of energy.
  27. Blogmas is my favorite holiday.
  28. That's so cool to think about that energy can't be lost or created even in the scenario of a massive rollercoaster.
  29. Thanks for discussing conservation of angular momentum between the balls as they role, great job.
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