Hot air balloons are very fascinating mechanisms in that they allow humans to fly without physically flying. Hot air balloons consists of a basket used to carry people, an envelope (the top piece), and a burner which consists of several megawatts is also present. When heat is released from the burner, it creates buoyancy. This is because the hot air is less dense than the cooler air that surrounds it. This is known as Archimedes' principle, which states that any object regardless of its shape that is suspended in a fluid, is acted upon by an upward buoyant force equal to the weight of the fluid displaced by the object.
I have always wondered if the experiment you always see on T.V. is actually possible and after further research, I realized that it is possible to charge your phone with a potato. The reason this is able to happen is because the potato acts like an electrolyte. When a galvanized nail and copper are inserted into the potato, they act as electrodes. Atoms from the galvanized nail- which is made of zinc- dissolves into the potato as a positively charged ion. This leaves two negatively charged atoms behind. These electrons then pass through the wire connecting the two electrodes and his flow of electrons is what creates electrical current which charges your phone.
It would be very cool to ride around using jet packs, but unfortunately some of Earth's physical properties limit our use of them. Unlike birds, humans are not aerodynamic meaning that it very hard to keep us afloat. To do this, we must solely rely on thrust and to generate this thrust, a large amount of fuel is needed. Unfortunately, the more fuel needed, the heavier the jet pack becomes. This requires more fuel to lift the weight and the problem just continues. Because of this dilemma, jet packs are not very practical and many last less than a minute in the air. In order to make them more efficient, scientists will have to find a way to make jet packs more fuel efficient.
While at work the other day, I was extremely bored so I decided to think of blogpost ideas. During this time, I was starring at the credit card machine and I thought it would be interesting to learn the physics behind credit cards. Credit cards are an interesting system that uses a magnetic strip to store information. Credit cards use Faraday's Law which allows current to go through the coil in it. This current goes through simple amplification and this creates binary code. The signal is then read by the computer. This is a simplified idea of how credit cards work, but in the end Faraday's Law, Biot-Savart Law and Ohm's Law are all used in the creation of a credit card.
The toothpick star is an interesting experiment in which a person aligns 5 toothpicks broken in half into the shape of a star. The toothpicks must be closely put together like the image shown however and the halves must be connected by a small piece of toothpick.
To make the toothpicks into the shape of a star, you must drop a droplet of water onto the center. Once this is done, the water will move into the toothpicks at the same velocity. This will cause the toothpicks to spread apart and mimic the shape a star as seen below.
This occurs because capillary action causes water to be absorbed into the toothpicks. The water moves into section that was broken in half and continues to move outward all the way to the pointed tip. The capillary action inside of the toothpick causes the toothpicks to glide as they straighten.
The northern lights also known as the aurora borealis is one of natures most beautiful phenomenons. Occurring in high latitude regions of the world near the magnetic poles, the northern lights are caused by high-energy charged particles from the Sun colliding with molecules in the Earth’s atmosphere. As solar wind passes Earth, Earth's magnetic field traps some of it. The electrons and ions that make up the wind travel towards the magnetic poles. The molecules that were already present in the Earth's upper hemisphere are now ionized because of the collision with the solar wind ions. They emit light by either regaining their missing electron or returning to their ground state.
Popcorn- especially movie theater popcorn- is one of my favorite foods. Until now, I have never thought to explore the science behind popping popcorn kernels. The metamorphosis from a kernel to popcorn involves several physics concepts including thermodynamics and bio-mechanics. To start off, the kernel must heat to a temperature above 100 degrees Celsius. The water inside then turns to vapor and forces its way into the hard endosperm of the kernel. When this occurs, the inside becomes a molten mass. The pressure builds and builds until the shell explodes. As soon as the kernel bursts, the starch cools and a delicious snack is formed.
I have always been fascinated by the idea of skydiving, so I thought it would be interesting to learn the physics behind it. When a person skydives, they are accelerating downward do to the force of gravity. Simultaneously, the amount of air resistance increases as the faster the skydiver falls. Once the force of air resistance is as large as the force of gravity, the skydiver no longer accelerates because the force of gravity equals air resistance. This equality is known as terminal velocity. To decrease terminal velocity which ultimately allows the skydiver to arrive on the ground at a safe speed, a large cross sectional area is needed to oppose the force of gravity and increase air resistance. This is the reason that a parachute is required. The large cross sectional area of a parachute slows the terminal velocity down to a safe landing speed.
In the instance of an emergency and there are no flashlights or candles present, a crayon can be used as a candle. A crayon is similar to a candle in that both are made of a variety of waxes. The only difference is that is a crayon is enclosed in a paper tube while a candle has a wick at the center. The paper tubing of the crayon can be used as a wick which allows the fire to burn steadily down the crayon. When a candle is lit, heat travels at a remarkably fast velocity toward the wax body beneath. Wax has a low melting point, so it instantly turns into a hot liquid which in turn burns the tubing of the crayon. The wax vapor also catches light and burns high above the candle- hence the appearance of a flame. Conduction then carries heat down the body of the crayon to melt more wax. The crayon burns until all of the potential energy is converted into heat, light and chemical waste. This can last up to 30 minutes.
The silver egg illusion is an experiment in which an egg is charged over a candle until it is completely covered in soot. Once the egg is completely covered, it should be dunked into a cup of water. The egg turns silver because the soot particles are hydrophobic so only the top part of the soot will be wet. The surface tension supports the water in between each grain of soot and a layer of air between the water and the soot forms. Because the surface of the water reflects light very well due to total internal reflection, the egg will end up appearing silver.
The answer is no. This image seems too good to be true, but this experiment is completely possible. The reason the pencils are able to go through the plastic bag without leaking is because of the material of the Ziploc bag. The plastic baggie is made up of polymers which are long chains of molecules that are flexible. When the pencil is pokes through the bag, it slips in between the chain of molecules. They then make a seal around the pencil which ensures that water will not leak out.
A couple of months ago, I watched Marvel's Doctor Strange. The physics of the movie really fascinated me, so i decided to delve deeper and learn about the physics of this very interesting movie. Doctor Strange discusses the idea of the multiverse. The multiverse is the hypothetical set of possible universes, including the universe in which we live. These universes make up everything that exists: the entirety of space, time, matter, energy, and the physical laws and constants that describe them. For instance, I could be eating pancakes for breakfast in one universe and cereal in another. Doctor Strange suggests that there are many parallel universes each with their own laws. They refer to these universes as dimensions in which different physical laws can be changed. Gravity can be 20 times stronger in one universe over another. Ultimately, these universes or dimensions can meld together and connections can be made between them. Doctor Strange also discusses the idea of consciousness and the mind-problem- the question of how the human mind and body interact. Scientist still have no idea how the human body and mind can coincide. To answer this question, it is important to study religion, psychology, and nuclear physic together. While people may use the words brain and mind interchangeably, they are two separate complex entities that work together and it is important to know why this is.
Today is the final day of Blogmas. For this very special day, I will find the frictional force of a child riding on sled. The average mass of a 10 year old child is 31.9 kg. To find the normal force I multiplied the acceleration due to gravity by the mass of the child and got 312.62N. The coefficient of between snow and plastic is .3, so the force of friction is between the sled and the ground is 93.786N.
For the 7th day of Blogmas, I will discuss how long it will take Christmas cookies to cool to 75° F once they are taken out of the oven. For this calculation I will use Newton's Law of Cooling. This law states that the rate of cooling is proportional to the temperature difference between the object and its surroundings; therefore, dT/dt = k(T-TC) with Tc the constant temperature. To find this calculation, I first found Tc to be 70° F because my house temperature is kept at this constant. Next, I used the separation of differentiable equations method to integrate the Newton's Law of Cooling Equation. As a result, I found the equation to be T(t)= Ce^(kt) + 70. To find the value of C,I set Ce^(kt) equal to 350° F( the temperature of the cookies immediately after they were taken out of the oven) and set t=0. With this information, I found C to be 280. I measured the temperature of the cookies to be 300° F after 5 minutes. Using this information, k was measured to be -.0393. After finding all the unknowns, I finally found the time it takes to cool to 75° F to be 102 minutes.
For the fifth day of Blogmas, I will discuss a specific scene in the movie Home Alone. At one point in the movie, two burglars enter the house because they believe nobody is home. Little do they know Kevin is still home and ready to protect himself. At one point, he swings a paint bucket and it hits one of the burglars. I thought it would be interesting to calculate the length of the string the paint bucket is attached to using the equation T=2π+(L/g)^(1/2). The period of the paint bucket is 4s granted there were cuts in the movie and human error ) and acceleration due to gravity is 9.8 m/s^2. With this information I found the length of the pendulum to be 3.97m.
For the fifth day of Blogmas, I will be discussing the physics of singing Christmas carols. When someone is singing, they emit sound waves. Because sound waves are mechanical waves, they are required to travel through a medium. When traveling through this medium, the particles vibrate creating a frequency which is measured in vibrations per second or hertz. In turn, the higher the frequency, the higher the pitch of the singer. The loudness or quietness of the singer is measured by the amplitude of the wave. The larger the amplitude, the louder the voice of the singer. Who knew so much went into singing Christmas carols?
A Christmas Story is an iconic Christmas movie, so today I decided to discuss the physics of one of its well known scenes. Ralphie's friend Flick is triple dog dared to stick his tongue to the pole by the kids in the school yard. Unfortunately, when he sticks his tongue to the pole, it gets stuck and the fire department must come to save him. The reason his tongue gets stuck is because the metal pole is a great conductor of heat. The thermal energy from your body is transferred into the pole faster than your body can replenish the loss of heat. As a result, your saliva, which is made up of 99% water, freezes due to the lack of heat on your tongue.
For day 3 of Blogmas, we are going to discuss the physics of Christmas lights. It is important to find Christmas lights wired in parallel because the set of lights will still work if one light blows. This way you will not go through the struggle of hanging all of your lights just for fail when you turn them on.Lights that do not work when one bulb breaks are wired in series. In series , electricity must flow from one bulb to the next. In a parallel, each light is on its own circuit to the power source. This is why one bulb breaking will not impact the overall circuit.
For today's Blogmas, I thought it would be interesting to calculate the force inflicted upon an ornament when it falls off of a Christmas tree. I have a 7ft Christmas tree so I decided to calculate the force exerted on an 35g ornament from this height assuming the ornament is placed at the top of the tree. F=mg therefore the force of the ornament when it hits the ground is .343N. I thought it would also be interesting to calculate the power of the ornament as it is falling. Using conservation of energy, I found the velocity of the ornament to be 6.47m/s. Then using the equation P=FV I found the power to be 2.21 watts.
For the first day of blogmas I decided it would be interesting to calculate how many reindeer it would take to carry Santa's load of toys. First, I found that there are approximately 2 billion children in the world (people under the age of 18). The average reindeer can pull about 136 kg and we can assume that children receive an average of 5kgs worth of gifts. Using this information, if can be found that Santa will need approximately 73.5 million reindeer to help him deliver his presents.
I have a little black shih Zhou poodle mix named princess who loves to jump on and off of the couch. I thought it would be interesting to calculate the velocity of my dog right before she hits the ground. To do this I used the conservation of energy theorem mgh=.5mv^2. The Masses cancel out, g is 9.8m/s^2 and the height of my bed is approximately .91 meters. After determining all of the variables, I found her velocity to be about 7.67m/s
Before writing this blog post, I could not think of anything to write. After sitting in front of my computer for about 15 minutes thinking of an idea, I started to stare at my toaster. Finally, I realized I could write about the velocity of toast when it pops out. I then proceeded to do further research and in the process I discovered that toast always lands buttered side down. The reason for this is due to the height of kitchen tables. Usually they are about waist height. As a result, the toast's period of rotation-the time it takes to make a 360 degree spin- is interrupted. When the toast falls off the table, it is only able to achieve a 180 degree spin. Assuming that the buttered side is facing up when it falls, that side will be the one to hit the floor. The only way to prevent toast from landing buttered side down is to double the height of the table.
Today is Halloween, so I decided to calculate the speed of a fun sized snickers when dropped into a trick-or-treater's bag. The mass of a fun sized snickers is approximately 17 grams. The average height of a 10 year old is 138.4 cm. With this information you can either use kinematics or conservation of energy. I chose to use kinematics and used the equation. Vf^2 = Vo^2 + 2aΔx. Assuming that the candy is dropped from rest, falls completely vertical and neglecting air resistance, the final velocity of the candy is 52.08 cm/s.
The Pringles Ringle is one of the latest challenges that people are trying to undertake. Thanks to physics, this interesting experiment is able to occur. The key to building it is to make sure that the base is sturdy. Once you have a solid base, you must insert a Pringle in between two other Pringles to achieve the circular shape. By doing this, the Pringle will stay clamped down because there is a force applied to hold it down. From there, you can keep building up and up The Pringles on top stay in place due to static friction.
Recently I watched a documentary about the possibility of teleportation. Scientists have discovered that through entanglement and superposition particles can be teleported transported to different locations. Entanglement is the idea that links the quantum states of two particles even when they are separated.The distance between the particles does not matter, so they can be on other sides of the universe and still be entangled. Many particles have been teleported by scientists recently because that is not the hard part about teleportation. The part that troubles scientists is maintaining entanglement. Superposition is the idea that a particle has unlimited possible states until you measure it. Once it is measured, you limit it to a single possibility. Because of superposition and entanglement, particles can be transported. This new knowledge is important because it could be the future for human teleportation. There begs the question however; if you are teleported, will it be the same person as before who arrives on the other side?
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