Posts Tagged ‘Physics’

After another one of my web escapades (I seem to be having a lot of those now that I have four frees in one day), I discovered Walter H. G. Lewin, a Physics professor at MIT.  He’s gathered a diverse following of people from around the world and inspired many to begin to explore the wonders of Physics. 

Professor Lewin spends an average of 25 hours preparing his awe-inducing lectures and demonstrations.  Some demonstrations include firing a golf ball cannon at a stuffed monkey to show projectile motion and placing himself in the trajectory of a 33-pound steel wrecking ball to illustrate Hooke’s Law while counting on the conservation of energy to keep him alive.  You can watch a VERY entertaining video of this and more here.   

The following are quotes from people who have been greatly influenced/intrigued by Lewin’s teachings. (New York Times article)

“Through your inspiring video lectures i have managed to see just how BEAUTIFUL Physics is, both astounding and simple,” – – 17-year-old from India

“I walk with a new spring in my step and I look at life through physics-colored eyes.”  – – Steve Boigon, 62, florist from San Diego

“Hi, Prof. Lewin!!  I love your inspiring lectures and I love MIT!!!”  – – 17-year-old fan from China

“You are now my Scientific Father. In spite of the bad occupation and war against my lovely IRAQ, you made me love USA because you are there and MIT is there.”  – – Physics teacher from Iraq

“Professor Lewin…made me SEE … and it has changed my life for the better!!  I had never taken a course in physics, or calculus, or differential equations. Now I have done all that in order to be able to follow your lectures.  I walk down the street analyzing the force of a boy on skateboard or the recoil of a carpenter using a nail gun. Thank you with all my heart.”  – – Mr. Boigon

Professor Lewin tells his students, “Your life will never be the same. Because of your knowledge, you will be able to see way more…”  He is a truly inspiring individual in the field of physics, someone who has made the subject both fun and interesting for millions. 

 Go here to view Lewin’s popular online lectures.



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A Despicable Parrot

I’m not sure if we’re supposed to do a blog this weekend but I will anyways…in which I explain my hatred for a certain bird. In a physics-related manner, of course.

Most mornings, I have the unfortunate experience of hearing my “neighbor’s” parrot squawking as I wait for the elevator to arrive at my floor. I do wish that there were a way to completely block out those sound waves. Usually however, I’m only mildly annoyed. But on stressful days (possibly let’s say…before AP exams?), my hands are just itching to cause the bird featherly harm.

But how could I be so cruel? That, my friend, takes us back to the old days…when I was still a 6th-grader in public school! To keep a long story short, it once again involved an elevator (weight and normal force!) except that this time I was about to exit it. Well, a certain stupid parrot flew in as the doors opened and…

Physics Interjection Time!! How do birds stay up in the air? Basically, a bird’s wings are shaped like an aerofoil and air passes over and under the wing. The air that moves over the top of the wing has to travel further to get across the wing, thus it speeds up. This causes the pressure to drop because the same amount of air is exerting its pressure over a greater area, pulling the wing upwards. Meanwhile the air going below the wing experiences the opposite effect, generates more pressure, and effectively pushes the wing up. Perhaps this reminds you of a plane…or maybe of a multiple choice question involving blowing air across a contraption with water inside.

Back to the story now…A certain stupid parrot flew in as the doors opened and bit down hard on my finger until it started bleeding (I still have the scars from this severe application of force) while clawing at my hair. It was most certainly not funny since I had to go to the hospital and all afterwards.

I’m obviously a pretty forgiving person. Especially when you consider that I’ve possessed a heavy 1000-paged Physics textbook for a year now and the parrot has not yet been subjected to the crushing effects of projectile motion.

But then again, it’s probably my “neighbor” that I really hate. He’s the one who let his bird fly around outside of his apartment (which so happens to be illegal!) as well as the one with the pathetic excuse: “My bird doesn’t like the color black. Black scares him. You have black hair. So um…yeah. It’s your fault, really. Want some chocolate?”

I’m not even kidding. -_-

Pretty Substitute Parrot!  It's only one bird that I can't stand.


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In Preparation

The AP exam is coming up!  This is how I feel:

And this would be very useful:


This not so much:


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Random Instances of Physics

It pains me to know that recently, my posts have become rather short and blah. And of course, I blame all of this on the upcoming AP exams. Anyways, this weekend was another one of those extremely busy and boring ones with few physics revelations. Which is most regrettably unfortunate.

First of all, I took the practice AP US History exam on Saturday. Overall, the exam was manageable. My general tiredness however led to some random thoughts more related to physics then history. For example, the word ‘tension’ in one of the multiple choice questions immediately produced an image of a free body diagram in my mind with weight = mg down and all that other good stuff. Too bad that has nothing to do with Bacon’s Rebellion.

As a second item of interest, my brother has proved to be a most amusing source of entertainment as of late. I should have known better than to provide him with the ammunition (aka Starburst) to practice projectile motion (where of course, kinematic equations can be used to determine distance travelled and time elapsed.) However, I was hardly involved with his laughable attempts at rapping in Chinese (so maybe I was playing Chinese music all day…) and singing opera. If there were a way to harness the energy of people like him, there would be no need to fuss over the dangers of nuclear power plants (fission goes boom!)

Yeah…now wasn’t that all very random?

Xin Li You Shu


Wo You Wo De Young


Chinese music!  But the awesome part is that the band singing the music is named Fei Lun Hai (Fahrenheit) !!!

So it’s completely related to physics, temperature, heat, and the like..  : D


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Convex Mirror Magic

Edit: Oh nos! I forgot to publish my post…until now.

So after my last orchestra concert ever (tears), I fell asleep on the ride home. Of course, since I don’t have a driver’s license yet, this was not a problem. : )

I didn’t wake up until we entered the parking lot and the first thing I found myself looking into was one of those round convex mirrors. The parking lot mirrors are very similar to the rear view mirrors on a car.

Because both are convex, the images created are virtual, smaller than the original object, and upright. Since everything appears smaller, it allows us to see a wider field of view than a plane mirror would. Which is of course extremely useful at times.

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On Friday, I worked the late malasada (Iolani Class of 2009!) shift from 8:15 to about 11 at night. I got to do quite a variety of things from selling malasadas in the front to squeezing the little balls of dough in the kitchen to washing the extremely oily pans. It was rather busy and I’m sure that entropy was increasing steadily under that white tent.

Anyways, I witnessed a plethora of physics at the fair on Friday. First, over half of the games involved projectile motion when aiming object A at/over/into/onto object B. So if you were equipped with your lovely kinematic equations, an invisible ruler, and a robotic arm, the games should have been child’s play.

And nearly all of the rides involved spinning about an axis and centripetal forces that point radially inward of magnitude mv^2/r. Unfortunately, they don’t go nearly fast enough. We should really have roller coasters instead. 😀

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Stress and Force

Seeing that I’ve have a throbbing headache for all of Sunday, this journal entry is rather late…Most likely this is all from an overload of stress. It’s very different from the physics sense of stress which I’m sure you all remember as amount of force exerted per unit area. Review time!

For much of this weekend, I’ve also been walking around at a constantish velocity carrying a VERY heavy box filled with tons and tons of pages. It was indeed very strenuous but according to physics, I wasn’t actually doing any work since the force applied and the distance the box moved were perpendicular to each other. That, however, didn’t stop me from getting an extremely sore back. Oh joy.

My Lovely Trophies!

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It’s at times like this when I’m almost certain that some nuclear explosion has gone off in my mind due to stress overload. At the very least, it must be possible to determine the half-life of my rapidly decaying brain. Hopefully, the rest of this post will still be coherent.

Anyways, Alois Kral died this week on Thursday, April 3rd. Exactly what were his contributions to physics? Kral was an electrical engineer whose work was used by The Manhattan Project, the team of World War II scientists who developed the nuclear bomb. Of course, Kral was not aware of this until after the atomic bomb was dropped.

The development of the nuclear bomb is of course a result of discovering nuclear fission, also known as “splitting the atom.” Fission occurs when a heavy nucleus breaks up into smaller ones, releasing energy.

The Hiroshima bomb, Little Boy, was made from uranium-235. By bombarding it with neutrons, induced fission is made possible. As the heavy nuclei is split up into intermediate-sized nuclei, the binding energy per nucleon increases and energy is released.

The process of fission is self-sustaining. After a single reaction, a few neutrons are released, free to then induce more reactions in nearby atoms. This will produce more free neutrons which go on to continue the process. Tada! A chain reaction is produced!

Indeed the destructive atomic bomb was not the best investment of our knowledge of fission. This just goes to show that knowledge can be dangerous. And so can secret governmental plans.

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