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DanDuguay

Optical illusions

Many of us enjoy looking at optical illusions, but why do our eyes lie to us?????

Although each illusion has it's own reason, and scientists still don't know all the reasons, it comes down to one thing. Our brain makes assumptions.

Our brain uses context of our surroundings to make split second assumptions. This is helpful in everyday life and back when we were hunters and gatherers and needed to make split second decisions in the wild. Our eyes don't show us what's really there just what we need to see. It uses the surrounding environment to make conclusions. This is done by using shadows, surrounding colors, and past experiences.

optical illusions are just a case of your brain telling you what you should be seeing, not what is actually there.

DanDuguay

2D Reubans tube.

In physics you learn about waves.

However, many people don't realize that waves are every where.

A rubens tube is a tube with natural gas pumped through it with holes in the top.

when a steady vibration is used on the tube, a standing wave is formed. It has nodes and anti nodes like any wave.

When you put a lot of vibrations through, like say music, the effect is very cool.

Most rubens tubes are just a linear single tube, in this video however, it goes into 2 dimensions

the result is amazing.

DanDuguay

Water and Sound

The video below shows a very cool experiment.

It shows how the flow of water changes when a vibration is applied.

water reacts very strangely when it is vibrated.

enjoy

DanDuguay

Resonance

Many cultures and spiritual factions speak of the importance of frequencies and vibrations. many cultures believe it plays an important role in nature.

Certain frequencies create geometric shapes

as the frequency increases, the patterns get more complex.

DanDuguay

Lift Forces

A fluid that flows past a surface of a body exerts a force on it. Lift is the perpendicular component to the oncoming flow, of this force. It is the opposite of a drag force.

Aerodynamic lift is different from other kinds of lift. Aerodynamic lift requires relative motion of the fluid. It usually refers to when an object is completely immersed in a fluid.

Lift is what makes it possible for a plane to fly. Lift is also used in Frisbees. As man takes to the sky, we owe much to the power of lift forces.

DanDuguay

When people think of the light bulb, they just think of Edison. That is not the case.

in 1802, Humphry Davy created the first electric light. He heated carbon with a battery until it started to glow. This was known as the electric arc lamp. This invention didn't work because it didn't last very long and was just too bright for an practical uses.

In 1840, Warren de la Rue enclosed a coiled platinum filament in a vacuum tube and passed an electric current through it. The design was based on the fact that the height melting point of platinum would allow it to operate at high temperatures and that the evacuated chamber would contain fewer gas molecules to react with the platinum. Although this was an efficient design, the high cost of platinum prevented it's use in the commercial market.

In 1850, Joseph Wilson Swan enclosed carbonized paper filaments in an evacuated glass bulb, but the lack of a good vacuum and adequate supply of electricity resulted in an ineffective producer of light.

There were many variations of a light emitting device before Edison, but he was the first to make a commercially viable model. Since there have been many different models, and there will continue to be changes in the future.

DanDuguay

What is Plasma?

Plasma is one of the four states of matter. You have plasma in your light bulbs, TV's, and the sun. Plasma is created by ionization. A gas is heated or put in a magnetic field. Plasma is a good conductor and therefore has a very small electric field.

Plasma is the most common state of matter in the universe. It is a very important pat in the fusion of light atoms. Plasma is often confined to a small region for fusion to take place in reactors. Plasma is a key part of solving the energy crisis we are facing.

Plasma is vital to the universe and is very important to us as humans. Plasma is often neglected by most people and that's not fair. Appreciate plasma.

DanDuguay

Continuing, another important part of the game is the weaponry.

To start, there is a weopan class called fusion rifles. The game offers no insight into how these guns work but the only assumption I can draw is that it has something to do with fusion. My theory is that there is some sort of nuclear energy generated by fusion and is somehow controlled and then fired from the wopen. There would be a lot of physics in the charging/splitting of atoms all in a short a series of short bursts.

There is also less exciting physics. For example there is a ton of projectile motion with the throwing of grenades or bullets. Also their is recoil in the guns. In this game you are a guardian, so I'd assume you are stronger than average but the odds are that there will still be recoil in the gun as a counter reaction of the projectile being launched (unless it's the ACR from MW2).

All in all, physics wise this is a pretty solid game. However, the story line is very week, the gameplay is repetitive, and the online can be pretty aggravating at times. That being said, Peter Dinklage is one of the voice actors, so you should buy this game.

DanDuguay

Destiny is a video game devolved by the company Bungie. Bungie has experience with theoretical physics after they made the Halo series. Destiny is one of the most expensive games ever made, which brings up an important question. Did they do a good job?

The first thing to look at is the little details. The capes the shadows, the lighting, and so on. In this, in my opinion, they did a good job. The game looks and feels fantastic. There are many flaws with this game, but all in all, they did a good job on the little things. The little physics is easy to miss but helps move the game along seamlessly.

Another aspect of the game is the sparrow. The sparrow is essentially a hover bike. We do not have one of these yet so I can't say how accurate they were on it. However, it looks and feels exactly how you think one would. It has propulsion on the back. Using Newtons laws it propels itself forward and uses Newtons laws somehow to keep it above the ground.

DanDuguay

Golf Swing

A golf swing is much like a slap shot in hockey. A good golf swing is vital in the game of golf.

A golf swing is almost all rotational energy. A higher velocity means more rotational energy. The more energy in your swing leads to more energy transferred to the golf ball. The more energy you can transfer to ball the farther it will go.

The angle at which the club hits the ball is also important. You want the face of the club to be completely flat when it comes into contact with the ball. If it makes contact at an angle, it will cause the ball to spin. The spin of the ball causes friction with the air resistance causing the ball to bend, and the ball will slice. This is much like how soccer players are able to bend the balls on shots and free kicks. The club is like the players leg, and the soccer ball is the golf ball.

DanDuguay

Slap Shot

Hockey is a fast paced sport full of physics. A prime example is the slap shot.

The slap shot is basically a large rotational force. The player is rotating his body and uses the stick as essentially an extension of his body. You can calculate the force by finding the impulse on the puck.

http://www.youtube.com/watch?v=bcielx6_ArQ

This is a video of Zedeno Chara at the 2012 all star competition

By simple physics equations, we can find out that his stick is rotation at 12.4 radians per second! That's pretty amazing

we also can find out that chara was able to bow his stick almost an inch. That creates a huge buildup of potential energy that snaps on the puck causing it to reach these high speeds!

DanDuguay

Guitar(acoustic)

Acoustic guitars work a lot like electric guitars and basses(see previous blog posts). They have six strings. The note the string plays depends on the frequency. The frequency depends on the length, mass and tension of the string. So that means that you'll have to tune and string your guitar differently depending on what strings you use.

When you play a note, the strings vibrate and produce a sound. The note produced depends on the frequency. This is pretty much universal in all string instruments. You can alter this by changing the length, so pressing down on the frets, the tension, use the tuning pegs, or the mass, by using a completely different string. I would recommend the first two options and not going to but a new string every time you tune your guitar.

However, the acoustic guitar has something that an electric guitar doesn't and that's a vibrating top plate. the vibrating top plate creates an air cavity resonance that will amplify the sound of the strings. the vibration of the strings gets to the bridge and the vibration of the bridge is what causes the top plate to vibrate.

The air cavity resonance can be affected by a lot of factors including the type of wood, as well as the size of the body and the hole. Antonio de Torres Jurado created a style of strutting that has the struts diverge from the sound hole on the top plate, creating a more sustained tone.

DanDuguay

Bass(electric)

People have heard electric basses for a very long time. People know you plug the bass into the amp and it makes sound. But people don't really know why.... until now.

First, if you take a look at a bass, look in between the bottom of the neck and the bridge. you will see the pickups there. these pickups are actually magnets. These magnets have a north and south pole. these magnets have a wire coiled around them. If you move a conductive material through a static field, then the material, the wire in this case, will induce a current.

By picking the string you are disturbing the field. The magnetic field then moves relative to the coil, which causes a current to be induced in the coil. the current goes through the bass and this is where the nobs come into play. This is where you can alter the sound of your bass before the signal gets to the actual amp itself.

The amp is broken down into to parts, the preamp and the poweramp. The preamp shapes the sound, this is where the gain, EQ, tone etc. comes into play. then the poweramp comes in. the poweramp just amplifies the sound. The only knob on the amp that really effects this part of the amp is the total output knob, or the volume.

DanDuguay

Bass Guitar

The bass guitar, or at least the physics behind it, works very similarly to a guitar.

The note that is produced by plucking the string has to do with the frequency. For example, if a string has a frequency of 440 Hz, than that would be an A note. You can change the octave of the note by either doubling the frequency, or cutting it in half. That means that it is still an A if it has a frequency of 220 Hz or 880 Hz.

The frequency of the note is determined by a couple of factors. The main factor is the length of the string. When you press down on a fret, you are shortening the length, and in turn raising the frequency. The 12th fret is always an octave up from the open string because its halfway down the string.

In addition to length, tension plays a role. when you tighten the string you increase the tension and that increases the frequency. The thickness also is a factor, the thicker the string the lower the frequency.

For more, www.bassplaying.com/physics-off-bass

DanDuguay

Bowling

Bowling has been a favorite past time for so many for so long. It is a sport that unites people from all parts of the world. Though the techniques may vary, some more unorthodox then others, some with spin, some with a simple flick of the wrist, the physics behind it is ever present.

Most standard bowling balls have weights in them, but there are two major types, symmetric and asymmetric. Though they perform very similarly, the asymmetric weights give the bowlers a little more tweak in their shot.

Getting curve on the ball is an important aspect of the game. This has a lot to do with the angular velocity of the ball. As the ball goes down the lane, the angular velocity changes and in turn, the ball starts to curve due to the force of friction of the ball on the lane

The difference in the weights has to do with how the axis of rotation goes through the weights. the direction and placement of the axis has to do with the moment of inertia. the different moments of inertia affects how the ball will go down the lane.

for more http://www.real-world-physics-problems.com/physics-of-bowling.html

DanDuguay

In 1936, A British zoologist named James Gray was baffled by the speed of dolphins. These dolphins were able to reach speeds of over 20 miles per hour! He examined the dolphins muscles and demonstrated that they weren't built to reach that kind of acceleration with drag. He chalked that up to their skin and that was the accepted answer..... was.

It turned out that Gray was wrong. Dolphins are amazing creatures and it turns out, Gray didn't give these water dwelling mammals enough credit!!!! A professor from the Rensselaer School of Engineering, Timothy Wei, proved that dolphins are quit brilliant.

Wei used technology original used for aerospace research. They tracked two bottlenose dolphins and video recorded them. The video showed the speed and direction of the water behind the dolphins so they could track the force the dolphins applied. It turned out these dolphins could create 200 pounds of force just from tail flapping! TAIL FLAPPING!!!!!!! THAT'S INCREDIBLE!!!!!! Olympic swimmers only generate 60 to 70 pounds of force :'(

In conclusion, dolphins are freaken awesome. They can generate massive amounts of force with their tails and propel themselves to incredible speeds. So next time you see a dolphin, tell it thanks, thanks for being a dolphin

DanDuguay

QuantumTunnelling

In Quantum Mechanics, there is a phenomenon called Quantum Tunneling. This is where a particle "tunnels" through a "barrier". I know you're probably saying, Dan! Why should we car about this??? well listen up, and I'll tell you.

This is important because this explains the nuclear fusion that occurs in the main sequence stars like the sun. Normally nuclear fusion requires a lot of energy to get these particles to collide but quantum tunneling uses a lot less energy. Quantum tunneling is very rare in stars like the sun, but the sun is so massive that the shear number of collisions make quantum tunneling very noticeable.

If we can find a way to make quantum tunneling much more frequent, we can effectively use nuclear fusion to create energy. This energy from nuclear fusion can help replace our reliance on fossil fuels. There aren't harmful byproducts from nuclear fusion so we can create a substantial amount of energy cleanly and effectively.

^^^^That is a good video that helps explain the basics of Quantum Tunneling if you want a visual representation or a different explanation

DanDuguay

Now that the History and base of Quantum Physics has been established, we can start the fun stuff. The first question of any good scientific theory is this, How can I prove this?

I'll start with my personal favorite, the double-slit experiment, also known as Young's experiment. A double slit is basically a diffraction grating. When light goes through a diffraction grating, well a basic double slit one, it has a banded pattern, the same thing happens with any wave. When a particle Is shot through a double slit, there should just be two lines the same shape and size of the slits. An electron, the smallest particle we know of, should have acted like any other particle and produced two lines the same shape and size of the slits, but as you can guess, that didn't happen. Instead, the electrons produced a banded pattern, like that of a wave. This proved that both particles and waves share common traits. This experiment was also completed successfully with larger particles which raises the question, could we eventually diffract ourselves? How big can we go?

Also, through experimental discovery, we have found that photons have momentum. For many this doesn't make sense, how can something with no mass have momentum? Well, scientists have found out that An objects momentum is also proportional to its Energy thusly explain why a photon has momentum. But this further shows the particle-wave duality of matter.

There is also black body radiation. Black body radiation is an electro magnetic radiation that is within or surrounds a body that is in thermodynamic equilibrium. Planck explained this as energy distribution and this could also be discrete. This is in part what helped him create the theory of the quanta, which is a building block of quantum physics and one of the things it explains.

As you can see, many experiments have been done to prove the duality of matter and have allowed Quantum physics to be universally accepted and be very helpful in understanding what happens when classical laws of physics break down.

DanDuguay

The first step in learning more about Quantum Physics is understanding what Quantum Physics means. Newton was a brilliant man and was great at explaining all the big things. But as things get smaller and smaller, these classical laws of physics break down. As we get down to macroscopic matter, they posses properties unlike those of bigger objects that Newton knew of.

The basic idea behind quantum physics is that matter has both wave like and particle like properties. Quantum physics deals with these duality of matter. The history of Quantum Mechanics goes back a long way and is quite interesting.

Quantum Physics first came from further understanding of light. At first, scientists believed that light was just waves, and matter was particles. Fairley soon, they found this wasn't the case. A scientist by the name of Max Planck, often referred to as the father of quantum physics, hypothesized that energy is absorbed and emitted in quanta. This hypothesis matched the black body radiation theory. he made an equation for this transfer of energy but he never thought of these quanta as tangible objects, more of an idea of explanation.

Einstein used Planck's discovery as a means to explain the photoelectric effect. Many experiments following not only proved that quanta exists, but they also have momentum and other traits of particles. So in Summery, at a subatomic level, particles and electro magnetic waves share properties and this wave-particle duality is the basis of Quantum mechanics.

DanDuguay

Tennis

Physics is ever prevalent in the world of sports. Tennis is no exception to that.

A tennis racquet, much like a baseball bat, has a sweet spot. A tennis racquet however, has 3 so called sweet spots. One is right by the center, and this is a node. A player will feel little to no vibration when the ball is hit in this spot. There is another sweet spot is at the center of percussion. The COM is located shortly below the node. The third spot is located even below that, and it is at this spot where you get the maximum bounce. The force you feel in your hand is due to the vibrations in the racquet so at the node, it makes sense that that is where the sweet spot for most is.

At the top of a racquet is the dead spot. It is at this spot that the ball barely moves. This is because all the energy from the ball is absorbed by the racquet and doesn't go back to the ball. You can feel, hear, and see when this happens.

DanDuguay

Compact Discs, aka CD's

CD's are something that everybody has had or has. But for such a universal product, we really don't know how they work...

Although the disc looks and feels flat, it actually is quite the contrary. On a CD is a ton of little pits. These pits have binary code in them. Then a Focusing laser goes over the pits, receives the code, and transfers it to a detection circuitry. The digital signal received is then converted to analog form by a D/A converter.

The Laser used is a semiconductor laser. There are also two prisisms, used in the system that help in the direction of light as well as multiple directions. The direction and the polarity of the laser light has to be manipulated in order to have a properly working system to play a CD.

As you can see, there is a lot more to a CD than just a spinning disc.

DanDuguay

Pinch Harmonics

Guitar players have many techniques in their arsenal. A guitar is a very versatile instrument and has the potential to make many different sounds, few more distinct than the pinch harmonic, also known as pick harmonic, or a squealy.

The basic technique behind it is that right after you hit the string, the string hits your finger. This cancels out the fundamental frequency and all overtones, except those that have a node at that location. Overtones that are a multiple of the intended overtone share the nodes of the lower tones. The Physics behind sound waves is extremely evident in all musical instruments, and pinch harmonics are a great way of manipulating physics in order to create a cool distinct sound that has changed guitar playing.

DanDuguay

Holograms

Holography is the art of 'lensless photography'. It is typically formed by reflected light captured on film. For example, a laser would hit an object. The object then reflects the light, and the reflection of the light is what is captured on the film. The images from a hologram contains more information than a traditionally photograph. The image is three dimensional and exhibits parallax.

Holograms have cool properties that aren't displayed in photos. My personal favorite is that in a transmission hologram, the one previously explained, every piece of the film contains the whole image. So If you cut of a tiny corner of the film, you see the same image as the complete hologram. So you can cut the film up into a hundred different pieces and the image would be the same on all of them.

Also, holographic images scale with wavelength. This is exciting because in theory, one could make a holographic image using x-rays, and view it using visible light. Although this has yet to be done, the potential is there and the benefits can be significant.

Holograms are often thought as movie props, or just a smoke and mirror science, but holography is a very important part of the optics field. Holography has the potential to do many things. Holography is used in the laser lab in downtown Rochester. Holography can be used you decrease the size of lasers, which will help in power alternatives in the future. Holograms, while very fun, are also very useful.

DanDuguay

Soccer

Soccer, the most popular game in the world, has a lot of physics under the surface.

The first is Newtons first law. The law of inertia. The ball stays at rest until acted upon. usually by a players foot. Then it stops only by an outside force. This could be friction from the field, air resistance, or another player. You can also factor in Newton's other two laws as well as momentum and a variety of others.

The best physics in my opinion however, is the bending of the ball on a shot, or the Magnus affect. The bend and dip on the ball is mostly because the player kicks the ball at a certain angle and velocity. The players put spin on the ball in order to neglect air resistance. On average, a shot is kicked at around 65 mph, after about 10 meters, the speed drops dramatically, and the drag on the ball will dramatically increase. As the velocity drops, the Magnus effect substantially increases and this is the major reason why the ball will dip and curve through the air.

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