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  1. One of the most important concepts in the movie, Interstellar, was the theory of relativity. And time, was a big factor in the movie. When the crew spent too much time on the water planet, Cooper was looking for a way to reverse it, asking if there was a way to reverse time. Of course we know that it is impossible in any way to go back in time, however I feel like the movie didn't stay true to that idea. When Cooper goes through the black hole he not only shakes Dr Brands hand but he also is able to influence a point in time that is at least 20 years. Also, they say that the wormhole they use to go to the other galaxy was put there by someone and they say it is humans. However, humans didn't have the ability to do that at the time meaning to put that wormhole there they must have gone back in time to do it. The movie doesn't stay true to the theory of relativity and I don't think it follows its' own physics. Also, the way they manipulate gravity and the physics of gravity is interesting to me. I think gravity was set up to be "time" in the movie, that is why they are able to change gravity to influence time. Gravity is time in the movie, instead of being able to go back in time through the black hole and just tell Coopers daughter the answer to gravity, the movie uses gravity and 5th dimensional beings to influence gravity or as I see it, the space-time continuum. The physics in the movie are, in some places, made up. I do not think you can change gravity and I think Interstellar's ending wasn't realistic as you can't go back in time.
  2. Team Name: Elladen Research Available Funds: $60,000 Vehicle Name: The Penultimate Mistake Vehicle Parts List and Cost: Mk1 Command Pod, FL-T800 Fuel Tank x8, FL-T400 Fuel Tank x2 TR-18A Stack Decoupler x2 LV-T30 "Reliant" Liquid Fuel Engine x5 48-7S "Spark" Liquid Fuel Engine Aerodynamic Nose Cone x4 Tail Fin x4 TT-70 Radial Decoupler x4 FTX-2 External Fuel Duct x4 Total Cost: $22,823 Design Goals: It was designed to reach 10,000 meters but as we easily surpassed that feat we decided to try to reach the moon. It is supposed to be a very fuel efficient rocket that can travel far. Launch Goal: We were hoping to reach the Mun and come back. Pilot Plan: The pilot is there to start all engines, decoup the fuel tanks that run out first, and conserve enough fuel to get to the Mun and back. Illustrations:
  3. Population concerns on Earth are leading scientists to inquire whether colonizing Mars is possible. As of now, over 78,000 people have applied to leave Earth forever and live on Mars. Mars One, a nonprofit organization, is sponsoring the colonization with a take-off date sometime in 2023. Out of the applicant pool, four will be chosen to send first to Mars. The first four will lay the groundwork for a permanent colony. Two years after the first four land, Mars One would send up more people to the colony. With the application process underway, it seems as though scientists have discovered ways for humans to survive on Mars indefinitely. However, this is not the case. Many, many concerns exist such as how will the colonists feed themselves? Will crops which grow on the Earth also grow on Mars? The first settlers of Mars will most likely be farmers. Yes, they will be astronauts; but, if survival is of any importance to them, they will learn to farm in order to eat. Research which has been conducted supports the idea that growing crops is possible in microgravity. However, those working for NASA do not know to what extent the gravity of Mars will effect crop growth. Also, Mars' surface only receives about half of the sunlight that the Earth's surface receives. Will plants be able to grow with limited sunlight? On top of the already limited sunlight, pressurized greenhouses would be necessary to grow crops. The greenhouses would block out more light. So, additional light would be necessary from other sources than the sun. What would power additional light sources? How would that power be generated and sustained? Radiation would also be a problem faced by those on Mars. Mars does not have as strong of an atmosphere as the Earth. More radiation reaches the surface of Mars than the surface of the Earth. Inhabitants would need a way to reflect the radiation or shield themselves from the rays. To live on Mars, man must master the art of agriculture in microgravity. Feeding the inhabitants of Mars is one among many more necessary tasks of survival. As of now, research is still being conducted. The 78,000 who have already showed interest in living on Mars are a bit stupid or extremely bold. With current technology man would not survive on Mars. I do not doubt though that technology will develop in the near future for man to successfully live on Mars.
  4. While we use percent error to dictate how far we off in class, there are far more efficient ways of defining the error of the set. Standard deviation, for example, given a value, will give rise to numbers that fall within one S.D., two S.D. and so on. "One can find the standard deviation of an entire population in cases (such as standardized testing) where every member of a population is sampled. In cases where that cannot be done, the standard deviation σ is estimated by examining a random sample taken from the population. An estimator for σ used when sample size is very large is the standard deviation of the sample, denoted by sN and defined as follows:" This method is effective for creating intervals for which certain points would have to lie within and give us the ability to decide on percent error for an entire group of values. The closer the value of S.D. approaches 0, the less the error percent is.
  5. Alright, this blog is for all you pyros out there. I couldn't help but want to delve a little deeper into the nature of fire, and what I found is pretty interesting. In actuality, fire is simply a gas thats hot enough to incandesce, which means give off blackbody radiation whos color is determined by the temperature. Very hot fires can on occasion even reach the plasma phase, where they become partially ionized. However, the average fire burns at about 1000F, which produces the characteristic red-orange flame that we all recognize. When burning objects, one can notice that they burn at different rates or perhaps colors. This is because the electron structure of some materials and compounds absorb the energy, exciting the electrons to a higher energy level and emitting different photons. A perfect example of this is sodium, which gives off a distinctive yellow color. In addition the surface area must be considered. For example, paper burns much faster than wood for this reason, for surface area gives the substance ready access to oxygen. Hydrocarbons are another thing that burns incredibly well, however this is for a much different reason. They give off more energy than cellulose, which produces the normal 1000F temperature, actually because they lack oxygen, so when supplied with it the reaction is much more drastic.
  6. Many common materials like wood, water, plants, animals, diamonds, fingers etc. are considered not to be magnetic but are in fact very slightly diamagnetic. Diamagnets repel, and are repelled by a strong magnetic field, and two of the strongest known diamagnetic materials are bismuth and graphite. Compared to the forces created by traditional magnets, diamagnetic forces are exponentially weak, however when arranged and prepared properly, can produce startling effects, levitation in this case. UCLA university has done multiple studies and found the most efficient and effective configurations for showing levitation in action. In the first configuration here we can see what seems to be a small golden cylinder floating in between two fingers. However in reality the magnet is levitated by a vertical superconducting solenoid electromagnet at a point at which the magnet is rendered vertically stable and however unstable in the horizontal plane. Thus, the floating magnet wants to move off sideways, but is however, for this reason is lined with bismuth and therefore repels the magnet overcoming the horizontal instability and the result is stable levitation. Another configuration is shown below. In this one, the magnet is suspended at a point far below the electromagnet where in this case it is vertically unstable and stable on the horizontal plane, unlike the example above. Diamagnetic plates are placed above and below to stabilize vertically. In the case above, human fingers were used as the diamagnetic plates to accomplish for real what magicians claim to do while only producing an illusion.
  7. There are two types of spin that a player can apply to a tennis ball, those being topspin and backspin. What prompted my thoughts on this idea would be my attendance of the University of Rochester tennis match today against Nazareth. As these advanced players made the ball skip and flip and kick every which way, my mind went crazy! :labmate) A topspin shot is hit by sliding the racquet up and over the ball as it is struck. By dragging the racquet over the ball, the friction between the racquet's strings and the ball is used to make the ball spin forward, towards the opponent. The shot dips down following impact with the court and also bounces at a lower angle than would a shot with no spin applied to it. As a ball travels towards a player after bouncing, it has natural topspin that is caused by the friction of the tennis court. When hitting a topspin shot, the player is reversing the spin of the ball, which requires more energy. This change in energy from potential to rotational kinetic energy allows the player to effectively execute the top spin shot. A backspin shot is hit in the opposite manner, by sliding the racquet underneath the ball as it is struck. This causes the ball to spin towards the player who just hit it as it travels away. What is very interesting about the back spin shot and has been proven by physicists all over the world is that hitting this shot requires only roughly about half of the raquet speed of a top spin shot, for to execute this shot the player does not change the rotation of the ball. The oncoming ball bounces off the court with topspin, spinning from top to bottom as it comes toward the player. When a player returns the ball with a slice shot the direction in which the ball spins around the axis of rotation is maintained. From the players perspective, it actually seems as if the ball is moving away from them.
  8. The theory of relativity encompasses two theories of famous scientist Albert Einstein: special relativity and general relativity. Concepts introduced by the theories of relativity include: -Measurements of various quantities are relative to the velocities of observers. In particular, space and time can dilate. -Spacetime: space and time should be considered together and in relation to each other. -The speed of light is nonetheless invariant, the same for all observers. Some, and to many most of the things that the theory of relativity introduces seem absolutely insane to many of those who hear it, although as technology advances more and more tangible evidence is being gathered to support the theory. In the field of physics, relativity catalyzed and added an essential depth of knowledge to the science of elementary particles and their fundamental interactions, along with ushering in the nuclear age. With relativity, cosmology and astrophysics predicted extraordinary astronomical phenomena such as neutron stars, black holes, and gravitational waves. However those are blogs of their own, so stay tuned.:love-struck: Special relativity is a theory of the structure of spacetime and is based on two main principles: -The laws of physics are the same for all observers in uniform motion relative to one another (principle of relativity). -The speed of light in a vacuum is the same for all observers, regardless of their relative motion or of the motion of the source of the light. General relativity is a theory of gravitation developed by Einstein in the years 1907-1915. The development of general relativity began with the equivalence principle, under which the states of accelerated motion and being at rest in a gravitational field are physically identical; something to which the simple mind would simply be insane. However when taken in to deep consideration, general relativity is really something interesting to think about.
  9. evan

    Neutron Stars

    Neutron stars are the collapsed cores of some massive stars. They pack roughly the mass of our Sun into a region the size of a city such as Chicago or another large american city. Neutron stars are some of the densest types of massive objects in the universe, at times reaching densities of over 10e14 g/cc. At these incredibly high densities, you could cram all of humanity into a volume the size of a sugar cube, giving one just a sense, even though it is simply impossible to wrap your mind around, the uniqueness of these entities. They are ideal astrophysical laboratories for testing theories of dense matter physics and provide connections among nuclear physics, particle physics and astrophysics, which have and will continue to lead to incredible innovation in our world. The strongest inferred neutron star fields are nearly a hundred trillion times stronger than Earth's fields, and even the feeblest neutron star magnetic fields are a hundred million times Earth's, which is a hundred times stronger that any steady field we can generate in a laboratory. These unique stars can and fairly regularly display phenomena displayed nowhere else on the entire planet. These include hyperon-dominated matter, deconfined quark matter, superfluidity and superconductivity with critical temperatures near 10e10 kelvin, opaqueness to neutrinos, and magnetic fields in excess of 10e13 Gauss, only a few of the simply amazing reasons why these nuetron stars are significant to us.
  10. Energy Transfer during Running When a person runs, their body must convert potential energy into kinetic energy. Potential energy is the energy stored within a system. Potential energy is used when the system uses kinetic energy to move in a horizontal direction. In the human body, potential energy is stored in the form of chemical energy. The chemical energy comes from the food that a person consumes throughout the day. The body needs a certain amount of calories (the energy from food) in order to perform certain activities. If the runner has not consumed enough calories throughout their day, they will run out of potential energy and become tired. This is because the body is not very efficient at retaining energy. Energy cannot be created or destroyed, but it can go elsewhere. As the person runs, most of their stored energy is released in the form of thermal energy. This is why people get hot and start to sweat when they do physical activity such as running. The body is heating up because it is literally burning the calories that it has consumed in order to keep moving in a horizontal direction. The runner will sweat, because sweating is the body's natural cooling mechanism. If the runner did not have the ability to sweat, the conversion of potential energy (the chemical energy) into kinetic energy which is released as thermal energy would cause the runner's body to overheat. The chemical energy that the runner consumes in the form of calories is also released in the form of sound energy. Every time the runner's foot hits the ground, energy is leaving the runner's body as sound waves emit from the impact of the runner's foot on the ground. Because energy is being released from the runner's body with every step they take, it is important for the runner to consume enough chemical energy in the form of calories prior to their run. The runner's body needs a substantial amount of calories as a reserve so that they will have more to burn as their potential energy is released throughout the run. Thermal energy is measured in calories. Calories are released from a given item as it burns. The amount of calories that are in something depends directly on the amount of chemical bonds that are broken and formed as it burns. For example, when a piece of wood burns, 3000 calories of thermal energy are released per gram. When an apple is burned however, it releases about 600 calories of thermal energy. Therefore, it is reasonable to assume that there is more energy available from breaking the atomic bonds in wood than from breaking the atomic bonds in an apple. One calorie is defined as the amount of thermal energy needed to raise the temperature of one gram of water one degree Celsius. Calories burn very slowly in the human body, and as they do, kinetic energy becomes available to the runner. 1 calorie is the equivalent to 4.186 Joules of energy. So, the more calories that the runner consumes prior to running, the more energy they will have available to them throughout the run. The runner�s energy can also be measured in the form of watts, or electrical power. One calorie also translates to about 4.186 watts. So, if the runner has 500 calories available to them, they are capable of producing over 2000 watts of electrical power. When the body uses the calories it has consumed, it is not very efficient at conserving this energy. As the leg muscles contract to propel the runner forward, about 75% of the chemical energy that the runner has consumed is lost due to the heat (thermal energy) that the body gives off as it converts it stores (potential) chemical energy into kinetic energy. Kinetic energy is equal to one half of the runner's mass times their velocity squared (KE=1/2mv^2). So, if the runner has a mass of 60 kg and wants to run at a rate of 9m/s, they will use about 2,430 Joules of energy. The runner is not able to change their mass, but they can increase or decrease their use of kinetic energy by increasing or decreasing their velocity. If the runner has not consumed a lot of chemical energy throughout their day, it would be wise for them to decrease their velocity as to decrease their kinetic energy and therefore use less of their stored potential energy. The power that the runner generates during their run depends on the amount of time it takes them to complete the run. If they decide to run a given distance, their power output will depend on how long it takes the runner to complete the given distance. The power of the runner can be calculated by dividing the amount of work that they do during the run by the amount of time it takes them to complete the run. (P=W/t). If the runner completes the run in a short amount of time, they will have a relatively large power output. If it takes them a long time to complete their run, the runner will not generate as much power. The amount of time that it takes the runner to complete the run depends on their velocity. An increased velocity will allow the runner to complete a given distance in less time. This will increase their power output, because they are doing the same amount of work as they would be doing if they ran the distance at a slower pace, but they will be completing the run in less time. Completing the run in less time requires the runner to expend more of their stored potential energy. So, when the runner decides to increase their velocity, they will increase their kinetic energy. They will also decrease the amount of time it takes them to complete the run, and therefore increase their power output. Because it requires more energy to produce a higher power output, the runner will need to consume more chemical energy (calories) in order to run at a higher velocity.
  11. We all love the classic movies of Star Wars, if you don't love these movies than your probably too cool to be reading this blog, but if your like us in physics c you can see the glaring flaw that represent themselves throughout the movies. Star Wars is in a different galaxy but the same laws of physics should be universal so while watching the movies you can pick up on certain aspects that are in fact impossible. 1.) One of the most basic flaws we can see in the movies is that during the epic space battles we can hear not only blaster fire, but the explosions and droid sounds such as in the end of the 4th movie and the beginning of the 3rd. Space is a vacuum and sound cannot travel through a vacuum because it needs matter to propagate, so because of this basic fact we can see that in all of the Star Wars movies we should not be able to hear anything while they are in space. Whether it be the sound of a blaster, explosion, droid, or the whoosh as a ship flies by, in space there should be no sound. 2.) Another flaw concerning the space battles of Star Wars comes from the explosions that occur. Not only should there be no sound, but an explosion in space would produce a flaming blast because of oxygen within the ship, but that blast would last for less than a second, and would only be interpreted from the human eye as a flash of light before the vacuum of space would extinguish it. As a vacuum has no oxygen it is impossible to have a fire in space, so the explosion caused from the ships would last less than a second before they disappeared, and as we can see in movies such as Star Wars 3 or Star Wars 1 where a fire catches on the ship and lasts for multiple seconds, those instances are impossible. 3.) Lightsabers and blasters cannot actually be made of light and they cannot shot lasers. If a blaster shot a laser it would than be impossible for anyone to see or dodge the beam as it would travel so fast that it would be impossible for anyone to the the light move. Also in the space battles, in a vacuum the laser is invisible because there are no particles to scatter the beam making it visible. So these storm troopers can't actually be shooting lasers, and the light sabers cannot be made of light because light cannot deflect the blasts from these guns. Lightsabers if made of lasers would require an object as dense as a black hole to stop the laser and make it turn back in on itself forming the shape of a lightsaber and we can safely say that is impossible to carry around. We can see that if lightsabers were lasers such as what the guns claim to shoot, they then would not be able to deflect opposite laser beams shot at them. Also if lightsabers were indeed just projections of light shot out, than it is impossible that they would go and than stop after about 3 or 4 feet unless there was some object there to block or reflact the light. If they were just beams of light shot out than they would shot out far far far far far far longer distances than just 3 or 4 feet. Lightsabers were also said to possibly be made of a plasma substance. While it seems possible to control this plasma substance the heat from the condensed material would cook the hands of the user. 4.)In the Space battles we all admire how the ships go around flying, shooting at each other, turning, spinning, but in reality we can see that the turns and spins shown in Star Wars are in accurate if there were actually space ships flying around. We see throughout the movies how the space ships make banked turns, such as the Millennium Falcon. A banked turn is a turn or change in direction where the aircraft inclines towards the inside of the turn. We can see on earth how banked turns are needed because the fixed winged aircraft need the air pressure in order to operate but in the vacuum of space there would be no need to use banked turns. With this idea there is in no fact need for wings in space. Ships such as the Falcon would be in fact the design of space ships, not like that of the rebel fighters in the 4th, because as you are in space and there is no atmosphere there is no need for wings to help you turn or control the ship. 5.) Another issue we see in these movies are the asteroids. As shown in the 5th movie as they escape Hoth the crew, Chewie Han Lea and the droids, fly into a asteroid field in order to escape their pursuers. We can see that due to physics these large asteroids should not be able to float together without crashing into each other. The field cannot contain such huge asteroids that just fly around because in reality they would fall into each other continuously ramming each other till they break down and the field is made up of smaller pieces of rock floating around large boulders. Also Han and Lea exit the ship within an asteroid, within a creature, not only is there no way a worm of some sort could exist in space living in an asteroid, there is also no way Han, Lea, and Chewie could exit the Falcon without putting on full space suits and expect not to explode in space's vacuum. Along with these five flaws we can see many more in the Star Wars franchise but the list can go on and on. There are certain concepts in the movies such as light speed and hyper drive which are impossible, but the movies play off the fact that we just don't have the technology now that can produce them thus they cannot be totally dis proven. The ideas and concepts above though are known facts about physics, space, and how the universe works and thus glaring errors in the Star Wars movie franchise.
  12. The Large Hadron Collider is the worlds largest and highest energy particle accelerator, and located in Switzerland as told to us from the Valentines day special of the Big Bang Theory. In the episode Leonard wins a trip to Switzerland over Valentines day to visit the Collider, and than must deal with the drama that unfolds as Sheldon tries to take Penny's spot on the trip. After watching the episode my own interests over the Collider were peaked and so I went online to research it. The LHC lies in a tunnel beneath the France-Swiss border near Geneva Switzerland. It is a machine made to and expected to address some of the most fundamental questions of physics helping us further understand the laws of nature. The machine is designed to collide opposing particle beams of protons or lead nuclei at certain energy levels. Built by the European Organization for the Nuclear Research the machine was made to test various predictions of high energy physics including the testing for the existence of the Higgs Boson (hypothetical massive elementary particle, only standard model particle that has not been yet observed, would explain the difference between the massless proton which mediates electromagnetism and the massive W and Z bosons which mediate the weak force) and other particles predicted by super-symmetry (a symmetry that relates elementary particles of one spin to other particles that differ by half a unit of spin). Over 10,000 scientists and engineers from over 100 countries and hundreds of universities came together to collaborate and build this device. The device is currently up and running but only at half power, the device will be active for a certain time at half power for many years and is not expected to be at full power until 2014.
  13. A team of researchers in Rochester have discovered a way to create metals that are highly water resistant. These metals can be used in applications such as rust-prevention and anti-icing. Before this, the same team created hydrophilic metals, meaning that they attracted water. These could be used for any applications where you need to take water from one place to another because the metal would just do it for you. Here is the article about Chunlei Guo and his production of super-hydrophobic metals. http://www.rochester.edu/newscenter/superhydrophobic-metals-85592/
  14. What's better.....being faster or being slower? Obviously faster. Have you ever wondered why some people are faster than others though? Are there trends? To understand the basics physics of running, you can think of your arms as pendulums. A pendulums velocity depends on the length of the pendulum, not the mass of the bottom. If the pendulum is shorter, the speed of the mass at the bottom is faster. Your mass at the end of the pendulum you can think of as your feet. Then proceed to assume that your legs are the pendulums. In order to shorten the pendulum...you have to bend your knees. Obviously you cannot run well with your knees locked, but you will run faster if your knees are bent. You can also think of your arms as a second type of pendulum. If you bend your arms at a 90 degree angle and swim them in stride with your legs, you will then proceed to run even faster.
  15. Superconductivity was first discovered by Dutchman and physicist Heike Kamerlingh Onnes, when Liquid Mercury was cooled to just 4.2 Kelvins!! (Using some very expensive Liquid Helium) While measuring the resistance of the substance, Onnes found that at this specific temperature, the resistivity of the substance quite literally dropped down to nothing. Zero Ohms. But whats the significance? Firstly, Onnes had discovered a material that would produce no heat when an electrical current flowed through it, which has huge technical implications. It is being discussed, for instance, whether superconductors can be used to levitate trains (the Japanese are researching a system called MagLev) or transmit power more effectively. Lesser known applications include more effective Magnetic Resonance Imaging (MRI's), more detailed SQUIDS (magnetic field sensors with a variety of applications, namely detecting brain activity), or even to shrink computers down by using smaller wires! What's more, a fascinating phenomenon coined the Meissner Effect goes into action whenever a magnet approaches the superconductor. ]The superconductor literally "mirrors" the approaching magnet. For example, if a north pole approaches the material, an identical north pole will be created in the superconductor, allowing the magnet to levitate at a careful height. A more detailed description of this effect derives from essential Electromagnetic concepts, namely the popular Lenz's Law. In a conductor, free moving electrons are always present. When a changing electric field is introduced to a conductor, these electrons seek to flow such that they perfectly cancel any changing field strengths. Unfortunately for the electrons, a great deal of resistance is present in most conductors, which prevents the flow of the electrons from canceling the change in magnetic flux. Thus, we become familiarized with a Lenz's law that provides usually only minimal resistance to flux change. Now the crazy physics begins. In a superconductor, a substance that has negligible resistance, these electrons are able to flow in such a manner that the changing magnetic field is completely canceled! Result: Floating magnets. Whats more, is that the magnetic field doesn't need to be changing for the Meissner effect to go into action! For this reason, the Meissner effect is different than normal diamagnetism (a term that refers to conductors that follow Lenz's Law). Holy Floating Magnets, Batman! This is an example of a sample cooled with liquid nitrogen, with a cubical magnet suspended above the superconductive material. You may have noticed the thin layer of mist above the conductor; this mist is actually condensed oxygen! This oxygen jumps up to the magnet when it gets too close and quickly evaporates. This is because oxygen becomes liquid at warmer temperatures than liquid nitrogen, and also because oxygen is naturally "paramagnetic" meaning its molecules are attracted to magnetic fields a just a little bit more powerfully than other elements. Superconductors, however, have a long way to go before they become reasonable. Numerous limitations exist. The hottest a superconductor has ever been is 138 Kelvin. The greatest challenge scientists face is getting the near perfect conditions of the laboratory into a household setting. But the future is coming! Its coming fast.
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