Jump to content

All Activity

This stream auto-updates     

  1. Today
  2. 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.
  3. A Valuable Lesson

    Last week, I went on vacation Monday-Thursday, and missed school. Friday, I had no idea what was going on, partly because of my usual lack of sleep, and partly because I was missing most of a very busy week of classes. Why was that week so important you ask? It was the week before midterms, where the classes which only last 1 semester have a sudden rush of work before they end, and it was the end of the quarter, where you suddenly realize you didn't hand in that essay that you should've, because your teacher didn't it grade when they should've, so they did it right at the end of the quarter and put it in the gradebook late, so you didn't realize that your grade dropped 15 points. This was that lovely week of reviewing everything in every class right before a massive test, all while catching up on that work you completely "forgot" to do. Back to my original point: I missed most of that week. Surprisingly, I've done fairly well on my midterms so far, even Physics (to my surprise), but that's because I already had most of my review material and (sort of) knew what I was doing. Sadly, I've screwed up in that part where you hand in work at the last minute, and my English grade isn't doing too well. Physics and Economics could be better too. So long story short, don't take vacations when you're really busy, because it can only make things worse. Also, don't try to do schoolwork on a plane. People will bother you, the noise makes it impossible to think, and the wifi is so bad that you can barely load a webpage. And if that webpage is webassign, then it simply won't work at all. Finally, one last lesson, don't expect it to be warm down South during a giant winter storm sweeping across the country, because even if you're in Houston, it can get below freezing. When I was down there, I checked the weather in Houston vs the weather in Rochester, and they were the same: 20oF. The entire city shut down because they weren't prepared to deal with the ice.
  4. How Different Pitches "Break"’

    Inspired by AaronSwims’s blog post title, I wanted to make my own post on a completely different topic. I wanted to focus on resonance and, while we briefly touched upon it last year, I feel the need to write about it. Resonance, in its most basic definition, is “the condition in which an object or system is subjected to an oscillating force having a frequency close to its own natural frequency”. So how do we see this every day? Bang a pot, pan, glass, even sheet metal and you will find that a noise of a certain pitch emanates from it. If there is little dampening (energy lost in other forms), then this frequency is close to that material or objects natural frequency. This natural frequency is what a system oscillates at when not disturbed by a continuous external force. A glass breaker sings loud so that the amplitude of air molecules moving is quite large and transferring more energy. If the pitch matches the resonance frequency, then the amplitudes add up, with the common example being compared to pushing a kid on a swing. Small pushes, over a given amount of time, will eventually lead to the swing having a much larger amplitude than when it started. In a material, such as glass, where it is brittle and prone to imperfections, the frequency and volume of a person's voice has the resonance which results in it shattering into hundreds of pieces. As always thanks for reading! - ThePeculiarParticle
  5. 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.
  6. Second Quarter

    These past few weeks have been some of the hardest weeks in high school. College applications were due during this quarter and once those were in, there was a sudden loss of motivation to do anything at school. In every class, I have noticed that I simply try and if I do not understand, I leave it and pray that it will not be important to know for the future. Sadly, this method has proved to be extremely unsuccessful. Midterm week has proved to me that I need to refocus myself for the rest of this school year or my grades will continue to plummet all around. I have self diagnosed myself with "Senioritis" which is curable with hard work and effort. I need to majorly fix my time management for the next semester and hopefully that will help me as well! Now on to studying for the rest of this week and praying that I can get a good grade on at least 2 of my next exams! Third quarter here I come! Until next time, RK
  7. Christmas Physics

    Even though it is well past Christmas, I figured why not use physics to try to prove a myth that many kids believe, the myth of Santa and his reindeer. While Santa is said to have magical abilities that allow him to deliver presents in one night all over the world, let’s pretend that Santa doesn’t have magic and he just obeys the laws of physics. So, Santa has to visit around 500 million houses in the span of 31 hours (taking into consideration different time zones and the rotation of the Earth) and deliver at least one present to at least one child. This means that Santa has to visit about 4480 houses per second, or spend .0002 seconds at each house. In order to travel fast enough to make this trip in one night, Santa would have to travel at around 6500 mph, which is completely doable (in a rocket). Since Santa would be travelling this fast, he would definitely need some type of heat shield for himself and the reindeer to endure trillions of joules of heat, or else he would just be a flaming ball shooting through the sky. Now, what about all the cookies and milk? Well, these could *easily* be converted into energy to fuel his sleigh using the equation E=mc2. So, I guess Santa could be real, it’s just not very plausible. It’s much easier to just stick with the Santa has magical abilities thing! Check out this fascinating article that goes much more in-depth than I do (it uses different numbers than me as well): https://www.snopes.com/holidays/christmas/santa/physics.asp
  8. Physics in Food

    At Boston University, the College of Arts and Sciences offers a class called Physics of Food/Cooking. This class combines learning physics with cooking which every person, even those who do not enjoy science, will fall in love with. The professor, Rama Bansil, teaches her students about the basic principles of thermodynamics, molecular physics with a little bit of molecular biology as well. She uses her cooking techniques with science to create treats and relate them to the curriculum. A perfect example of the idea of physics in food is presented in the video above with a coconut ice cream shell. They use liquid nitrogen to quickly freeze and eliminate the ice crystals that would form with a slow freeze. In doing that, they end up with a creamy coconut ice cream shell! I really want to take a class like this in college! Until next time, RK
  9. ICE ICE BABY!

    “Alright stop, collaborate and listen Ice is back with my brand new invention Something grabs a hold of me tightly Flow like a harpoon daily and nightly Will it ever stop yo I don't know Turn off the lights and I'll glow.” Why would I start this blog up with Vanilla Ice’s song “Ice Ice Baby”? Well Ice is the subject of today’s blog. “BUT TPP, HOW MUCH CAN YOU TALK ABOUT ICE?” I hear you ask off in the distance from behind your computer… well, honestly, a lot. I love ice, from chilling hot summer drinks, to fishing through it in the winter. In the Northeast, we get so much of it that you have to not fully hate it to live up here. Did you know there is more than one type of ice? Actually, there are at least 17! Under normal atmosphere and temperature we see hexagonal ice (or ice I). By changing pressure and temperature, the other forms can be created from here. The table below shows how they are formed. And with hexagonal ice forming polar bonds, it is able to expand up to 9% of its original volume in freshwater. We have all seen the damage this can do in potholes in the road, but how much force does it have? Well ice can withstand 43,511 pounds per square inch before it turns into ice II. So it is very strong, to the point that instead of continuing to expand, it turns into another type of ice altogether. This table shows a few of the different types of ice and their required conditions they need to form. The first property I want to discuss is why ice is so slippery. The truth is dry ice is not very slippery at all. The problem occurs when melting begins. This can be either due to increasing temperatures melting the top layer, or the amount of pressure being placed on its surface. Pressure has much more to do with the phenomena than you think as the more pressure something applies to the surface the pressure increases and results in a lowered boiling point. This is an obvious problem for drivers in the winter who slip and slide due to the weight of their vehicles. But, while it can cause chaos on the roads, it is what gives joy in ice rinks everywhere. Ever wonder why skates are blades? That's because it centers all of one's body weight on an incredibly small area in order to maximize psi. The result is a smooth glide across a thin layer of water. The second property is that it floats on water. I'll gloss over this since it has been ingrained in us since 3rd grade at the latest, but the truth is that this property is one of the most important. If ice simply sank and became denser whenever it froze then it would make it much harder for life to survive during times of cooling. An example would be the microbes found underneath Antarctic ice which haven't seen the light of day in millions of years. The fact it floats helps us in the summer with our hot drinks, but also when I ice fish in the winter. I can confidently place myself on four inches of black ice (not white ice which is much weaker as air is trapped in it) and I know due to its strength and buoyancy my bodyweight will be safely kept out of the freezing water. Ice is never something I mess around with, just because ice is thick in one spot doesn't mean it is anywhere else. I guess I'm just trying to say don't do anything dumb… on a physics board… filled with incredibly bright kids. Anyways, that's my rant about ice. There's other topics I may touch in the future, such as the triple point of water, but for now I'm just going to chill out. I also have some awesome videos for you guys reading this far. This video, while sounding eerie and like the ice is breaking, is actually the sound of ice forming. As it expands and grows it creates tiny pressure cracks which give off these odd sounds. This clip shows the full range of the ice singing from bass tones all the way to high pings. This video is taken from planet Earth and shows another odd behavior of ice as it forms in salt water. As always thanks for reading! - The Peculiar Particle
  10. How Different Pitches "Break"

    We are now only a few weeks out from the unofficial start to the Major League Baseball season, pitchers and catcher reporting. This day, February 13th, 2018, begins the spring training process that leads up to the start of the season on March 29th. My realization of the nearing call, lead me to think about how many different breaking and off-speed pitches that exist in baseball today. What i discovered is that only two main factors contribute to how pitchers manipulate their throws to be more than just a simple thrown ball. Every curve-ball for example moves based on the position in which the ball lies in the pitchers hand, and the spin applied. Of these two factors, spin seems to have the greatest effect and the most physics tucked away. The physics of pitching starts by looking at air as the fluid it is and knowing it fallows Bernoulli's law. This states that an increase in the velocity of a fluid decreases its pressure. When a pitcher throws a curve-ball they spin the ball to use this principle to do deceive the batter. A baseball has three axis on which it can spin, X. Y, and Z. Forward spin along the x-axis is known as top spin while backwards spin along the x-axis is what we know as backspin. These two spins carry great effects on balls as they introduce rotation either in the direction or against the direction of travel. As the ball flies through the air, the bumps on a ball cause drag that allows the sin of a ball to change the pitches placement and direction. As the ball spins in either direction it causes a pressure differential on either side of the ball due to Bernoulli's principle. Then combine topspin and backspin with a spin along another axis, it is easy to see how all other pitches are created, simply by some combination of these spins. This all holds true until we consider the one, rare, odd ball pitch: the knuckle-ball. The knuckle ball has little to no spin on it and thus is considered by some to be a cheap pitch and many are not taught to throw it. Simple thought justifies that it would be simple to hit a ball with no spin since it wont move like previously stated. That's where things get complicated. The knuckle-ball benefits from chaotic fluid dynamics where each imperfection in the balls surface leads to an impact on its flight. Since this is so subtle, it only requires a slight change in the balls path to completely change the balls direction. As a result, the ball wiggles uncontrollably and unpredictably fooling even expert batters.
  11. Bowling...

    Most people think of bowling and think about how much fun they have with their friends and family. For me, I think of bowling for a team with a focus on hitting every pin down for a clean game. Clean games equal good scores and good scores equal a happy Rachel. (Clean games are games with all strikes and spares) For the past 6 years now, I have bowled for the school and on weekends, I participated in a league to improve. Every season has its ups and downs and currently, I am in a hole that I cannot seem to get myself out of. Consistency is a huge key in bowling and if you do not hit your target on the lanes consistently, everything can go downhill. The game of bowling is also about choices. "Do I use this ball and stand at the center dot and hit the second arrow or do I throw this ball and stand 4 boards to the left of the center dot and hit two boards to the left of the second arrow?" A lot of factors impact your bowling but, one thing will always remain the same: physics. Every lane, no matter which oil pattern, has Newton's Laws all over it. The force that is equal to the mass times the acceleration shown through a grown man throwing a ball that can knock down the pins with a stronger force compared to a six pound ball that is thrown by a little girl. When the darn 10-pin in the corner does not fall down (the worst pin on the planet), the second law is acting on it because there is no outside force meaning that it will stay at rest. Finally, the third law is shown when you life the ball from the return, you are putting a force on the ball and the ball is putting a force on you. Same with the approach that you walk on, you put a force on the ground and the ground puts a force on you. Well that is all for now... Until next time, RK
  12. So Who is Gauss?

    At the beginning of this past unit starting electricity, we learned about Gauss's Law and how it was going to be the start of a lot of work in the future with it. I, as do many, need to spend some more time and focus on getting this figured out soon because I have a strong feeling that this will be something I struggle with for the rest of the year if I do not understand some of it soon! Although this idea was named after Gauss, Joseph-Louis Lagrange started work on this law 40 years prior to Gauss. They both put contributions towards Gauss's Law which relates the distribution of electric charge to the resulting electric field. Now, this post is really going to be about the man that created the law, Carl Friedrich Gauss. Gauss was a German mathematician who huge contributions in many areas including algebra, geophysics, mechanics, electrostatics, magnetic fields and optics. Gauss was a child prodigy when it came to math and science. Growing up, he was a perfectionist and a hard worker who devoted his life to mathematics. He had two wives and six children who, in the course of his life, all died except for one of his children. Due to these tragedies, Gauss lived a depressed and miserable life until he died at 77 in 1855. Gauss's work paved the way for a whole new understanding in the field of electricity and magnetism which now allows us high school physics students to somewhat understand some electricity in physics! I do not understand it now, but I am now determined to learn and focus on this! Until next time, RK
  13. Fire is Wild

    Many describe fire as one of humanity's greatest discoveries. It helps to keep us warm, provides light and energy, and can the remaining coals can help to cook a mean dutch oven stew or cobbler. Fire works by combustion, requiring fuel, oxygen, and an energy source to kick start the reaction. Though this sounds more towards the chemistry side of science, fires in the wild have mastered physics in order to spread and speed up their consumption. Most wild fires tend to seemingly prefer to spread uphill when compared to another other possible direction of travel. The reason for this leads to the physics of wild fires. Fire, like the sun, releases radiant energy to its surroundings. As a fire burns at the base of a hill, the fire radiates energy to the combustible matter in its path. This allows the fire to supply its own energy source to start a new combustion reaction or to feed its current reaction. Studies of wild fires in California, found that for every 10 degrees of slope on a hillside, a fire can double its speed.
  14. Yesterday
  15. The Bizzare Way Butterflies FLy

    With this recent warm weather that we have had, i have had thoughts of spring and a world booming with plant life. With spring time in Rochester comes rain, sadly, and everyone's friend the Monarch Butterfly. Butterflies also have an enormous wingspan compared to their body size, and research shows that most butterflies can fly with damaged wings, or even as little as half of their current wing span. All those times as child when your parents told you not to touch a butterflies wings or wont be able to fly, that's right, they lied to you. So this brought me to question the size of their wings as towards advantages, and also lead to an interesting discovery about butterflies. First, did you that butterflies fly by contracting and relaxing their bodies rather than directly flapping their wings? This creates a more bizarre flight pattern making harder for predators to catch butterflies. Try it, their tough little buggers. As for the matter of why their wings are so large, its because their larger wingspan makes them more agile in the air allowing them to turn faster in the air. Butterflies have over evolved their flight and have one up'ed the animal world. They think they're better than us. Can't trust butterflies.
  16. Sonic vs The Average Hedgehog

    I wish I could have a pet hedgehog... sadly my dad won't even let me have a fish
  17. Sulfur Hexafluoride

    I cannot stop laughing at this
  18. A Couch... And My Hair

    I love looking at the little sparks with one of my blankets at night! I think it is super cool!
  19. Levitation?

    After my thoughts of flying in the last blog post, I got thinking about the idea of levitation. I started looking into this idea and it actually came up that there is currently a group at the University of Bristol in England that is trying to use sound to levitate objects off of the ground. This idea was first brought up by a Russian physicist, Andrei Geim, who counteracted the gravity on Earth to float a small frog. Physicists are now working to increase the size of what they can levitate to humans and then maybe even cars! They have determined that if they are to place an object at a certain point within a sound wave, the force of gravity and the force of the sound wave will cancel each other out and leave the object floating. The "mini tornado" sound waves work in such a way that it counteracts the gravity it normally feels. Although this has only been tested on very small objects so far, hopefully it will progress to larger items and even humans soon. This is probably the best thing that I have seen all day and maybe we will see more progress with this and find people levitating in the near future! Until next time, RK
  20. The Incredibles

    Last night, my sister brought up the sequel to The Incredibles which got me thinking about another topic for a blog post. The movie has a lot of physics examples in it; however, there are several examples of where some laws of physics are broken. Each family member has a superpower that makes them unique but they break laws of physics that could not actually be broken in real life. Mr. Incredible has super strength which allows him to pick up cars and stop trains. When he stops the train from falling off of the broken track, he has to put a force on the train equal to the force it is traveling at in order to stop it from falling off. Although this part of it is true, I think that everyone knows that a human could not simply stop a train in the way the Mr. Incredible did in the movie. Next is Dash, the son that can run at extreme speeds which allows him to get away with putting tacks on the teacher's chair without him noticing. In his time to shine, Dash managed to run so fast that he ran across the water. If he were running this fast, why would he have to worry about getting shot at by the bad guys because their machines should not have been able to move as fast as he did. Again, I think we all know that no human can actually run across water like Dash did in the movie. This movie makes me wish that I could have a superpower, too. I think I would want to have super strength or the ability to fly (or both). Since that will never happen, I am just going to keep on dreaming! Until next time, RK
  21. A Couch... And My Hair

    Yo same! that happens with me too
  22. The Physics of Thor's Hammer

    I'm guessing all of us in this class have seen at least one movie with Thor in it, right? (And if you haven't, don't talk to me) As anyone who is familiar with Thor would know, he carries a hammer (until the latest movie, but we won't talk about that) that only the worthy can lift. Other members of the Avengers like Iron Man, The Incredible Hulk, and Captain America have tried, but all have failed. How is this possible? Well, according to Marvel, the hammer weighs about 42 pounds. That's certainly something The Incredible Hulk could lift. However, when a force greater than 42 pounds is applied upward, the hammer still remains at rest. Well, friends, apparently this very special hammer has the ability to change mass by emitting graviton particles. This changes the gravitational field around it so it can be light enough for Thor to pick up, but too heavy for others. So, now what I want to know is... where can I get one?
  23. Sulfur Hexafluoride

    One of my younger brother’s favorite shows to watch is Mythbusters, and repeats are on almost every day. Well, a couple of days ago I saw a video about inhaling sulfur hexafluoride. Everyone has heard someone talk after inhaling helium from a balloon, they sound really funny because their voice is very high. The effect helium has on the voice is because it is much less dense than air. It causes the speed of the sound of your voice to increase, whereas the frequency of the vocal cords doesn’t change. Inhaling sulfur hexafluoride has the opposite effect of helium, it causes your voice to go extremely deep, like Darth Vader. This is because it is much denser than the air we breathe in, causing the speed of sound of your voice to decrease while the frequency stays the same. It is really entertaining and amusing to watch someone talk after inhaling sulfur hexafluoride!
  24. A Couch... And My Hair

    In the winter my bedroom gets really dry, so when my PJ's rub against my sheets, you can see small sparks all over my bed when the room is dark!
  25. One of the world's favorite characters is Sonic the Hedgehog, a blue hedgehog who runs incredibly fast. Sonic can run at around Mach 15, which is 5,104.4 m/s (11,509 MPH). That is incredibly fast! He also weighs about 34.93 kg, which means that at full speed, his kinetic energy is about 455,048,817.3 J. If a normal hedgehog which weighs about 0.91 kg, were to run at its top speed of 5.3 m/s, its kinetic energy would be around 12.8 J. This is about 0.000003% of the energy that Sonic generates.
  26. A Couch... And My Hair

    Since we just started electrostatics, I thought I'd do a blog post about something related to that. So we all remember the demonstration with a balloon and someone's hair, right? I know we did it in physics last year, but it's probably something most of us did as kids. Well, my brother and I used to do something a little different. Notice, I said used to, so I tooooootally wasn't doing this last week. Instead of a balloon and our hair, we used a couch. I know that sounds really weird, and I honestly have no idea how we came up with that idea. But when we rubbed our heads on the back of the couch, our hair would stick up like crazy when near the couch. Sometimes, you could even see sparks between our head and the couch. Like with the balloon, when the hair is rubbed on the couch, electrons moved from the hair to the couch, giving that part of the couch a negative charge and the hair a positive charge. This is why the hair is then attracted to the couch. It looks really funny with my long thick hair. I know you guys are all dying to try it now, so go find a couch and rub your head on it!
  27. Need a Laugh?

    Thank you for existing, physics memes.
  1. Load more activity

Terms of Use

The pages of APlusPhysics.com, Physics in Action podcasts, and other online media at this site are made available as a service to physics students, instructors, and others. Their use is encouraged and is free of charge. Teachers who wish to use materials either in a classroom demonstration format or as part of an interactive activity/lesson are granted permission (and encouraged) to do so. Linking to information on this site is allowed and encouraged, but content from APlusPhysics may not be made available elsewhere on the Internet without the author's written permission.

Copyright Notice

APlusPhysics.com, Silly Beagle Productions and Physics In Action materials are copyright protected and the author restricts their use to online usage through a live internet connection. Any downloading of files to other storage devices (hard drives, web servers, school servers, CDs, etc.) with the exception of Physics In Action podcast episodes is prohibited. The use of images, text and animations in other projects (including non-profit endeavors) is also prohibited. Requests for permission to use such material on other projects may be submitted in writing to info@aplusphysics.com. Licensing of the content of APlusPhysics.com for other uses may be considered in the future.

×