# cool thing i learned in physics today...

Discussion in 'The Lounge' started by colbystephens, Apr 19, 2007.

1. ### colbystephens1 ton statusGMOTM Winner

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well, we were talking about light waves and discussing how electromagnetic waves (light) carry energy. well, in the diagram that follows is an instrument that, when placed in a vaccuum, when you shine light on the white faces (these have black faces on the opposing side) of the pieces which are attatched to the disk, it will rotate around the axis (shown as the triangle). this is because momentum is associated with light waves and, long story short, because black absorbes light and white reflects it, the momentum of the light waves pushes on the white faces causing the toy (such as in the figure) to rotate counterclockwise.

if it is not in a vacuum, the black absorbs the waves and the air molecules heat up infront of the black faces. this causes those molecules to bounce into the black faces and the toy would rotate clockwise instead of counterclockwise because the bouncing air molecules have more momentum than simply the light... interesting!

2. ### TSGB1 ton status

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I'm strange. I've had a grasp of odd and end things like this since Jr. High. But put an algebra problem in front of me, and I'll pull my damn hair out.

3. ### colbystephens1 ton statusGMOTM Winner

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then it's good that i left all the calculus/algebra out of the description - or we'd have a dedicated CK5 anti-hawk in the crowd...

4. ### TSGB1 ton status

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More like a drooling mental health patient...

5. ### Jagged1 ton status

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Speak for yourself bud.

6. ### broncoman65241/2 ton status

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i sleep in physics...lol. hte only reason i stay awake someitmes....is that one girl right now its not too bad though...were learning about electicity and wirign and ****. (EASY) LOL its like another auto class but just elec.

7. ### kgillyk51/2 ton status

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So???...What way does it turn if you flush it down a toilet in Belgium?

8. ### colbystephens1 ton statusGMOTM Winner

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don't sleep too long - that subject takes off and goes crazy w/ gaussian surfaces, integrals and derivatives beware!

9. ### broncoman65241/2 ton status

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yeah i know...i try not too. lol. my teacher sux ass. we basically teach ourselves. its the end of the year ive learned about force, work etc etcetc, and now electiricy that is ALL weve learned

10. ### colbystephens1 ton statusGMOTM Winner

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i know what you mean - i've had a few instructors like that.

11. ### RussellLB7 Tahoe StatusPremium MemberGMOTM Winner

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When I wind up with an instructor like that, I pair up with the hot, but dumb, blonde in the class, and teach her whats going on -- Not only does it majorly re-affirm it in my mind by explaining it to someone else 30+ times in a row, it also gets you major browny points with the hottie when she eventually gets it!

12. ### broncoman65241/2 ton status

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haha i never thought of it like that! LOL!

13. ### XHitman3961/2 ton status

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yeah, to hell with all that crap. flux, induced magnetic and electrical currents, fields, inducers, light refraction (mildly interesting) and everything else involving physics II. but then again i, too, have a case of the professor who should be a wal-mart greeter. oh, and in a class with over 150 students, there's only one hot chick. damn engineering college...

14. ### colbystephens1 ton statusGMOTM Winner

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i don't know man, maybe you shouldn't be blaming the engineering school but perhaps be blaming oklahoma... j/k

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