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baseball00

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  1. What Does the Gold Foil Experiment Mean?

    The gold foil experiment is the famous experiment conducted by Ernest Rutherford that we all learned about in chemistry class. This experiment proved that atoms are made up of mostly empty space. In fact 99.9999% of an atom was proven in this experiment to be empty space. Lets say we could eliminate all that empty space by condensing the parts of an atom together. How much weight could we fit in a small space such as a single teaspoon? Over a billion tons! This idea is common when studying astronomy. At the end of a stars life, it collapses and explodes in a supernova explosion. The remaining mass that the supernova leaves over is so dense that the star begins to collapse in on itself. As a result of this, electrons fall into the nucleus and smash into protons becoming neutrons; hence the name neutron star. This animation shows a star going through a supernova explosion. The accuracy of this animation is highly questionable but it certainly looks cool.
  2. The Doppler Effect

    The Doppler effect occurs in everyday life more often than you may think. It is the change in frequency or wavelength of a wave relative to a moving observer. In this animation a car has sound waves that it is emitting. As the car starts to move the wavelength of the wave becomes smaller on the side of the car that it is moving toward and larger on the side that it is moving away from. An observer on the left side of this car would hear it gradually become higher pitched. An observer on the right side of the car would hear it gradually become lower in pitch. The Doppler effect is true for light waves as well. This is wear the terms red-shift and blue-shift come from. Blue light has a higher frequency than red light; therefore if an object appears to be becoming more blue that means it is moving toward you. If an object appears to be turning more red than it is moving away from you. This is only noticeable on very large scales like when observing space. Because of the Doppler effect, scientists have determined that our universe is expanding since most objects in space are red-shifted relative to earth.
  3. Refracting vs Reflecting Telescopes

    The first telescope to be invented was a refracting telescope. A refracting telescope works by using converging lens to collect light. A refracting telescope has a convex lens that bends the parallel light that is coming into it to a focal point. That focal point is where an image is formed of what is being observed. At that point is the eyepiece that you look through to see the focused image. This diagram shows the inside of a refracting telescope. A reflecting telescope was invented after that refracting telescope by Isaac Newton. A reflecting telescope works by collecting light and reflecting it off of a concave mirror. The light that is reflected comes to a focus point where a flat angled mirror reflects that light up toward an eyepiece where the viewer sees the image. This diagram shows the inside a reflecting telescope.
  4. Magnetism

    Our latest unit in Physics was learning about magnetism. A magnetic field occurs when charged particles are moving. According to greek legend magnetism was discovered by a Shepard in a field as he suddenly felt a force of attraction coming from the ground as he wore shoes with iron on the bottom. The substance he found later became known as magnetite, after the place it was found, Magnesia. Another common magnetic substance that was well known was lodestone. This was used in ancient China by the first emperor to protect his palace. Huge blocks of lodestone were placed outside the entrance. This was meant to attract soldiers in armor so they were prevented from entering the village. In ancient Egypt magnets were used for entertainment by doing (non) magic tricks. They would place objects above a magnet so that they would repel so the object would seem to be floating in mid-air. It wasn't until the 1500's that magnetism was scientifically investigated by William Gilbert who discovered that the earth itself is a magnet with a magnetic north pole and south pole. Not too much later came Friedrich Gauss and Charles Coloumb, where our understanding of magnetism became less of a mystery. In 1861 James Clerk Maxwell used equations to relate magnetism and electricity.
  5. MLB opening Day!

    Major league baseball opened up the season this week and there were some exciting stats and physics involved in the 11 games that were played on Thursday the 29th. Here are some of the great physics highlights of opening day. Giancarlo Stanton hit 2 home runs on his yankee debut. One of his home runs leads the league, so far, in exit velocity off the bat: 117.4 mph. With a launch angle of 19.8 degrees, its projected distance traveled is 426 feet. Jordan Hicks of the St. Lous Cardinals has the fastest pitch of opening day at 101.6 mph. At this speed, Hicks produced a spin rate of 2,233 rpm. While this ball had a great amount of kinetic energy, it also had a large amount of rotational kinetic energy as well. The highest spin rate of 2,649 rpm was thrown with a 99.2 mph four-seam fastball by Aroldis Chapman. The farthest home run of the season so far is by Matt Adams of the Washington Nationals. He hit the ball 460 feet with a velocity of 109.3 mph and launch angle of 28.6 degrees. Physics is always relevant in baseball. Throughout the 2018 season there will be a lot more exciting stats while it is only the beginning.
  6. Electric Motors in toothbrushes

    Want to make brushing your teeth even easier than it already is? Try using an electric toothbrush that uses an electric motor to rotate the brush back and forth to scrub your teeth better than ever. How does it work? On all the electric toothbrushes there is a battery at the bottom. This is used for a source of voltage which creates a current. As the current goes through the circuit, it reaches a point where it experiences a magnetic field. This creates a force upward on the circuit causing a net torque in the clockwise direction as shown in the diagram. As the circuit rotates 180 degrees, the direction of the current switches; therefore, the direction of the force switches, so it turns around the rotation. This back and forth motion gets transferred to the brush which is why it is so effective in making teeth super clean and white.
  7. Is Math Invented or Discovered

    Anybody who has ever taken a physics class knows that math plays a very essential role in solving problems that explain the laws of the universe. The question is: has math always existed and waits for us to discover it, or is math our own invented logic? There are many mathematical phenomena that are mysteriously found to come up in nature such as the Fibonacci sequence, and the numbers e and pi, that would be evidence of math being a preexisting language of the universe that we are continuing to discover. There are also some people that would say numbers are just a way for our conscious to understand how things work. Aliens might not know what math is but still have there own unique way that they understand the universe without using numbers in any way what so ever. The argument can go both ways but one thing is for certain: for humans, math has never failed us in our journey in studying the universe, so whether it is made up or not, it works!!
  8. Superionic Ice

    Water and ice molecules on earth have a distinct molecular structure that gives it the properties that it has; however, under different surrounding pressures, the molecular structure can change, resulting in the formation of superionic water. Superionic water differs from the ice/water you and I know so well. "Regular" ice has molecules that form a V shape with two hydrogen atoms and one oxygen atom. As pressure increases, these atoms get squeezed into different shapes. A property that superionic ice has is that it is a conductor of electricity; however, unlike most conductors, the current is carried by positively charged ions instead of negatively charged electrons. This substance was just a theoretical idea until recently when the University of Rochester's OMEGA laser tested the theory and was successful in creating superionic ice. They knew this was a success because the molecules were able to conduct electricity. Due to the opaque color of the molecules when electricity was ran through it, it was determined that it was, in fact superionic. If it had a shiny look to it, the researchers would have known that it couldn't of been superinoinc because that would mean that negative electrons were carrying the current. The pressures that were applied to the ice by the laser were almost 2 million times the atmospheric pressure of earth. This is the amount of pressure that planets Neptune and Uranus have.
  9. Escape Velocity and Black Holes

    Every massive object in space has an escape velocity. Escape velocity is the minimum velocity an object must have in order to escape the gravitational strength of a particular planet or any large body in space. The earths escape velocity is about 11.2 km/s. This means that an object must travel 11.2 km/s to escape its orbit around the earth. Reaching this velocity is a very big challenge when dealing with space travel. The more mass a body has, the more gravitational attraction it has; therefore, the escape velocity becomes faster. A black hole's escape velocity is so high that nothing can escape its gravitational pull; not even light. That is why its call a "black" hole: there is no light coming out of it so you can't see in it. A black holes escape velocity must be greater than 300,000 km/s (the speed of light). How can in object have this must mass to generate this much gravitation? When a star reaches the end of its life, some of them collapse all the way down to a single point, maintaining it's mass. This means that it becomes infinitely dense. Our sun does not have the potential to eventually become a black hole because it is too small. Stars that become black holes are 20 times the mass of the sun.
  10. Super Bowl LII

    Super Bowl LII is nearly 2 hours away. The Patriots and the Eagles are both great teams with lots of talent. Not only will I be watching the game, but the physics of the game as well, being a physics student. Some things worth taking note of are the kinematics of kicking a field goal, the forces that are felt while getting tackled, the kinematics of deep passes made by Tom Brady and/or Nick Foles, among many others. The minimum height needed to complete a successful field goal is 10 feet. A typical field goal is kicked anywhere from 30 - 40 yards away from the goal post. Depending on how windy it is will determine the correct angle and velocity at which the ball should be kicked. Lineman can weigh up to 300 pounds, so running into them is not fun for running backs. When the defensive lineman start to charge over the line of scrimmage they posses a tremendous amount of momentum. While running backs also have the ability to reach a great amount of momentum due to there ability to reach very high speeds, they don't have the mass to match the linemen. Also when running backs come in contact with lineman it is usually at or behind the line of scrimmage, not allowing them to pick up a high speed to match the momentum of the large linemen. There is more than just throwing a ball up in the air really far when quarterbacks toss those amazing 60- 70 yard completions near the out of bounds line. Quarterbacks have to time it perfectly so the ball reaches the target at the same time the wide receiver arrives at the point where the catch is made. A successful completion all depends on the speed of the wide receiver and the trajectory at which the quarterback throws the ball into the air. Hopefully Super Bowl LII brings us lots of cool physics to observe.
  11. The Many World Theory

    The many worlds theory suggests that there are an infinite number of universes that exist outside of our own. This theory was developed by physicists studying quantum particles. In quantum physics some things can have properties of either particles or waves and there is no way to determine which one. This influenced the many world theory because in quantum mechanics things have a wave-particle duel nature, so each fate of a particle is carried out, but just in different universes. According to this theory you are not the only you. You are living in an infinite amount of universes, each with different possibilities of you. All the possible alternatives that ever existed in history exist in a different world. Anything that could have possibly occurred in our past actually did happen in a parallel universe. Many scientist refer to these universes as giant bubbles floating around in space as shown below.
  12. Photons from the Sun

    Light from the sun takes approximately 8 minutes to reach us on earth; however, that does not mean that those particular photons are 8 minutes old. The suns light is produced in the center of the sun when massive amounts of energy is released. The sun has a radius of 696,000 km. The distance between the edge of the sun and the earth is 149.6 million km. From this information you would come to the conclusion that it takes less time for a photon to reach the outer surface of the sun than it would to reach the earth. The truth is that it actually takes much longer for a photon to travel from the center of the sun the the edge. This is because as a photon is released it travels through the sun with a lot of stops along the way. A photon can only travel a certain distance inside the sun without being absorbed and released by an atom. As a result, it can take up to millions of years to finally reach the surface of the sun. A cool way to think about this is that the light from the sun can potentially be produced millions of years plus 8 minutes ago.
  13. Running Super Fast with Usain Bolt

    Usain Bolt: the fastest man alive is 6'5" and 207 pounds. Being this large is rare for a sprinter because 207 pounds takes a lot of work to accelerate. To make up for this disadvantage he sprints quite differently than others. His average stride is 2.44 meters long. This means that in a 100 meter race he only takes 41 strides. That saves a lot of time because the more times that you come in contact with the ground, the more time it takes to complete the race. In the World Championship in Berlin, Bolt's closest competitor made 2.22 meter strides, resulting in about 45 steps through the 100 m race. Bolt finished in 9.58 seconds(the world record), with an average speed of 10.44 m/s and maximum speed of 12.42 m/s. Long strides is not the only thing Usain Bolt does differently to improve his speed. Every time bolts feet touch the ground he rotates his body about 20 degrees from the vertical forward as he pushes off from the ground. Being so tall he has a lot of gravitational torque when he leans forward. He uses this torque to his advantage by allowing his body to free fall forward. Take a look at Bolt's record breaking race in the world championship in Berlin.
  14. Physics in soccer

    Cristiano Ronaldo is one of the best soccer players in the world. He is known for jumping extremely high to score headers. Headers are goals scored by using your head to hit the ball into the goal. This is a very useful skill in soccer because if you can jump higher than all the defenders than you can hit the ball without the defender getting in your way. Just how high does he jump? In a sports science analysis, Ronaldo jumped in mid air with his hands on his hips. The result was a height of 44 cm in the air. This is about average for a soccer player, so this would not be successful most of the time when going for headers. A second test had him jump as high as he can with a running start. The result was a staggering 78 cm. That is higher than the average NBA player! In order the accomplish this he jumps off of the ground with a force of 50 N. In one of his most famous goals, against Manchester united, Ronaldo's head reached a height of 263 cm which is equivalent to 8 ft 6 in.
  15. What is Gravity?

    For centuries scientists have studied the cause of gravity. Even though there have been theories that have proposed reasons for gravity, we still don't know for sure what exactly causes it. Isaac Newton developed the idea of gravity in the 17th century. He said that it was just a force of attraction that all objects naturally had toward each other. It wasn't until the early 1900's when Albert Einstein came up with his theory of relativity that explained the reason why objects attract each other. The theory says that massive objects warp space-time which causes these objects to fall toward each other. What is space-time? Space-time is the combination of space and time into one thing. This sounds really strange but every time it has been tested, it has never failed;however, that's not to say that it is completely proven. One way you can prove this is if you go to the top of an extremely high building, time actually speeds up. This is because the further you are from the earth, the less warped time is. That goes for space as well. There is much more to this theory. This is just a very brief explanation of how Albert Einstein tackled the idea of gravity.

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