Physics Blog

Blog 13

Dylan — Mon, 09 May 2011 03:03:43 +0000

Hey guys! I’ll give you three guesses what that is. No I won’t. It’s a polarizer for a camera. While it might not look like there’s a piece of glass there, there is. And it’s not just any sort of glass, it is a polarizing filter, specifically, one designed to block out horizontally oriented light rays. A small prize like those found in Happy Meals if you can tell me what you would call the filter, then! Anyways, the important part to notice is that in this image it doesn’t look any darker within the circle than outside of it. This is due to the fact that there is no glare. Do you remember the lab we did in class that dealt with filters and sunlight, et cetera? Well, this is practically the same thing, but with real world applicability. Next time you pick up a camera, check the front of it. You might just see a Canon polarizing lens strapped to the front of it.

Blog Twelve

Dylan — Thu, 21 Apr 2011 00:32:07 +0000

So there is this cat. His name is Stefan. Stefan has spent his entire life in the bathroom. You see, Stefan is a rather shaggy cat and overheats quite often if he leaves the cool tile floor of the bathroom. So, there he resides. There is food in the cabinet, a toilet in the corner, and a shower in the other corner; everything he could ever need. But, if you must know, Stefan is also an opera singer. He loves to sing. He sings, and sings, and sings. Normally, he sings while he is in the shower to ward off the oppressive feelings of misery that overcome him as he is pelted by water (which he absolutely despises, but realizes is necessary for his hygiene). So, the other day, Stefan was singing in the shower while glancing at the mirror. He has such a strong and powerful and controllable voice that Stefan is actually capable of matching the natural resonance of the mirror with his own vocal magic. If he concentrates extra hard and sings super loud, he can make the mirror warp and form sinusoidal waves from his sound waves. It is really quite the sight to see. (The same thing can be seen if you bump up the bass too much in your car, the rear-view mirror starts to warp and jiggle like a go-go dancer.) Anyways, Stefan was singing in the shower to rid himself of misery while watching the mirror starting to warp, when all of a sudden, his father walks in. Stefan’s father says, “Stefan! Why is your singing so poor?!” Stefan, astounded- never having heard someone say his singing is bad: in fact he thought it sounded rather good- retorted, “Father! My singing sounded fine to me! Whatever is the problem?” To this, the father responded, “Stefan, did you not know that it was only the acoustics of the shower that made you sound nice? The sound waves were bouncing off the shower walls in such a way that you sounded very nice, but when I opened the door the most horrendous sound reached my ears. Stefan, I’m afraid you’re not cut out for the opera. You only sound good in the bathroom, dude.” Then, Stefan wept quietly. He climbed out of the shower and toweled himself off. He murmured, “I suppose physics is cool. It enabled me to warp that mirror and that was pretty nuts, but at the same time my dreams were crushed when my father told me I’m only good at singing because of the shape of the bathroom. Shucks.” Then he went to sleep.

Blog Eleven

Dylan — Wed, 16 Mar 2011 08:48:35 +0000

I’m getting vaguely sentimental now that we’re into blog 11. That is a lot of blogs. Nonetheless, I will probably forget about this blog soon after completing physics class. Maybe I will stumble across it as an agéd adult and say “wow that was a lot of blogs”.

Digressions aside, I curbed to peer pressure. Mrs Chen convinced me that it would be a good idea to wreck my phone charger in the pursuit of scientific gratification. Luckily, three years ago, my uncle once left a go-phone here before he went back to Canada. This is the accompanying charger. Regardless, it was an emotional moment. Don’t you dare belittle my moment of emotion.

Above is the remains of my ruined charger. There are lots of things and a few dakines and some stuff and quite a few dohickeys, but one aspect of the charger-innards that stood out was the white burrito-looking package towards the top of the charger assembly. “Boy”, I thought, “wouldn’t it be dandy if that were a solenoid like we’ve dealt with in class?!” Try as I might, though, I was unable to remove the tape and get a closer look. So you’ll just have to take my word for it that when I run my fingers across the tape I can feel the subtle ridges of coils of wire beneath it. No I am not lying. The tape is probably there for insulation ~~so the solenoid doesn’t get cold~~ so no other wires come in contact with the coils and mess it up. This aspect of the charger is crucial as it alters the voltage from a shockingly high (haha..) 120 volts to a meager 9 volts, or whatever this ancient candy-bar phone requires.

Overall I found it really interesting that the lab wasn’t the only place that physics was applicable. I’m learning new stuff every day!

Bonus Picture

Dylan — Wed, 02 Mar 2011 10:28:01 +0000

Blog 10

Dylan — Tue, 01 Mar 2011 08:22:24 +0000

Our family has recently taken steps to become less energy-dependent by installing CFLs in place of our old incandescent lightbulbs. This bulb was taken from my personal desk lamp. While it is swirly and cool and white, it also is importantly lower wattage. Lower wattage means less power usage in parallel circuitry like that in my house. Less power usage means less KwH in use, meaning lower power bills! The good thing about CFLs is that they light in a different manner than incandescent bulbs, they are brighter with the aid of chemistry. This is really helpful when I am ‘burning the midnight oil’ working hard on homework. If we could switch out all of our bulbs, we could significantly reduce our bill!

As a study question, do you know what would happen if my house were wired in series instead of parallel? Would power usage still be less? The changes in responses is intriguing.

Blog Nine

Dylan — Sat, 29 Jan 2011 22:14:22 +0000

This is me sailing my boat. Woah, yeah, super cool. I was concentrating kind of hard because it was windy, and I didn’t want to flip over. But what I didn’t realize was the grave danger I could possibly have been in. As you can see, there are clouds in the sky. Clouds mean moisture, rain. Clouds can also mean lightning. When it turns dark and stormy, and lightning is imminent, this usually means that there is a charge discrepancy between the charged sky and the neutral ground, or in this case, water. When charges are unequal, crazy stuff goes down. Electrons can jump from the charged area to the neutral or oppositely charged area, in some cases causing static electricity and in others causing lightning!! Lightning is really just a huge version of static electricity. Given that water conducts electricity, it was probably not the best idea to go sailing when lightning was possible. What’s more, my boat had a huge lightning rod on it; the mast! That means, out of anywhere near me, I was the most likely to be hit by lightning, since lightning rods draw the attention of lightning by providing the shortest and easiest root for the electrons to transfer over. This was really sketchy! Luckily it all worked out and I didn’t die.

Blog 8

Dylan — Mon, 10 Jan 2011 01:33:02 +0000

Torque. T=Force (Lever Arm). Since the ruler is 12 inches long, and the fulcrum is at 6 inches, and since the ruler is of uniform thickness and mass throughout, both the lever arms and the torques are equal and opposite. On the right, the torque is clockwise, while on the left, the torque is counterclockwise. The lever arm is 6 inches for both torques, as is the force, so the torques are exactly equal; they cancel each other out. If the fulcrum were further to the left, though, the lever arm on the right would be greater than the lever arm on the left, which would increase the torque on the right, which would cause the ruler to start rotating, since net torque would not equal 0. Most likely I would drop the ruler unless I compensated quickly. This equation gets even more difficult when you have to deal with things like weights and lines too!!

Blog 7

Dylan — Mon, 13 Dec 2010 01:23:19 +0000

Ah, the typical fan picture. Similar to the spinning fairy thing in our lab, centripetal force is present here. The fan blades rotate around the center of rotation, the aluminum base. The centripetal force is provided by metal bars connecting the blades to the center, so I suppose the centripetal force is the metallic bonds between the metal molecules. Regardless, fans provide a very good example of Fc= M(v^2/r). Since radius is always constant (no, this fan is not telescopic), velocity is the only variable changing. As velocity increases, as shown in the equation, centripetal force increases as well. If velocity were to decrease, centripetal force would decrease proportionately. Therefore, theoretically, if the fan spun fast enough, the metal would pull apart and the fan blades would all travel in straight lines tangential to the circle they had formed. That would be havoc! Good thing I have a strong fan.

Bonus!

Dylan — Sun, 12 Dec 2010 23:32:09 +0000

This is a banked curve. Found while cruising down Mulholland drive in L.A. Man, it was so much easier to make the turn because of the banking!

Bl6g

Dylan — Mon, 29 Nov 2010 07:26:14 +0000

In this photo, a white SUV speeds towards another identical SUV which is stopped. A collision is imminent! Let’s say these two SUV’s do collide a few seconds after this picture was snapped. If SUV 1 is going 5.0 m/s, and SUV 2 is going 0 m/s, and there is no friction, and SUV 1 doesn’t brake at all, and their bumpers are really really hard, then theoretically SUV 2 (if it doesn’t have any brakes, anymore) will be moving forward at 5.0 m/s after the collision. This is also assuming their masses are identical. Anyways, all that assumed, the conservation of momentum stays relevant. I digress, conservation of momentum is always relevant, it just takes different forms. M1V1 + M2V2 = M1V1f + M2V2f

This picture provides a good illustration of an otherwise fairly abstract theory, though, I think. Even though this theory rarely applies in real life, such as driving, it is very visible in controlled lab experiments with balls and frictionless rollers. Braking messes things up, though.