Left (your right). Right (your left). Center.

Get your pads, mouth guard, and helmet,were tackling relativity.
The Special Theory of Relativity as developed by the one and only Albert Einstein...includes only inertial reference frames (those that are not accelerating, i.e. superman flying at a constant velocity equivalent to that of a flying bullet, or Wonder Woman at rest in an airport wishing her invisible jet wasn't broken)

Everything's relative. Length, time, position, order of events, etc. EVERYTHING.

And experiments prove it. We can put an atomic clock on a plane, and have it measure the duration of the flight and it will differ from the amount an atomic clock on the ground measures. There is no "real" time, no "correct" position, no "actual" height, no "true" order of events. When did you read this blog? Before or after I wrote it?
(Next time you don't have your homework ready tell the teacher it wasn't assigned yet.)

It all derives from The Speed of Light Postulate: The speed of light in a vacuum has the same value, c, in all directions and in all inertial frames. Independent of the source motion.

side note, attempts to accelerate a particle to the speed of light have failed because when relativistic momentum is no longer proportional to velocity. so as the particle’s speed increase the acceleration caused by a given force continuously decreases. So no matter how great a force is applied as a particle reaches c, its acceleration reaches 0 and you get this graph:

-http://startswithabang.com/?p=1176

(this is from another physics orientated blog, so if you’re looking for someone who updates more regularly… also is an astrophysicist with degrees and experience and whatnot…and links to lots of other blogs. not going to lie. its pretty sweet. Props where props are due.)

Now fun stuff.

put Frederick on a train moving at a constant rate and Ishmael on a platform at rest. They will measure different spans of time it takes Freddy to pass, different lengths for the platform, and argue over whether two actions are simultaneous. What's fun is that as ridiculous as that seems, its true and the equations aren't even that hard.

Challenge question: How far does light think its traveled when it leaves the sun and goes to the earth? Hint: we measure it to have traveled 1 AU = 149, 597, 870.7 Km.

I know that is the absolute worst hint in the world since you’re already on the internet and could have googled that in about two seconds like i just did. maybe the equation would be a better hint.

Equations to use:

x’=vt’

delta t = delta t’/sq root of (1-u^2/c^22)

x’=(x-ut)/sqroot(1-u^2/c^2)

(probably these, I haven't actually worked this out yet so I cant make any promises)

Best Wishes!

There were Real Physicists!

Physics is in one word REAL. Its also broad, varying, growing, and most importantly…INSANE. Lets begin.

“You are invited to develop a theory of bottle washing. Assume that you have a large volume W of clean water and a bottle of volume B which contains a small volume D of dirt. W>>B>>D. When water is put into the bottle the dirt dissolves immediately, and when the bottle is emptied a small residue R of solution remains. How do you get the bottle as clean as possible using all the water?”

quoted from Thinking Like a Physicist: Physics Problems for Undergraduates written by the staff of the Physics Department of the University of Bristol, and edited by N Thompson. Problem 15.

That is a REAL problem on a REAL test at the REAL University of Bristol, although I think by Raymond’s definition the professor that gave it wouldn’t be a REAL physicist no matter what research or degrees they have earned.

Lets begin again.

“You are invited to develop a theory of bottle washing. YES!!!! I SCORED AN INVITE TO THE PARTY OF THE WEEK! Assume that you have a large volume W of clean water Delicious! and a bottle of volume B is that B-Awesome or Super-B? which contains a small volume D of dirt. time to get dirty! W>>B>>D. Gotta love the much greater than signs. When water is put into the bottle the dirt dissolves immediately, That's convenient, and when the bottle is emptied through direct drinking by yours truly (after being poured through a Brita *commercial plug*) a small residue R of solution remains Bummer . How do you get the bottle as clean as possible using all the water?”

I’m thinking…

A: tear off the bottom of the bottle by magic, sylar’s cutting ability, brute force, or whatever other device you prefer. then begin a continuous pouring of water through one end and emptying through the other.

2: Fill up the bottle, empty it. Repeat until W=0. Note that the bottle will never be 100 percent clean but D will approach an asymptote = 0.

III: Quit while you’re ahead. throw away the bottle and keep whatever container W is initially contained in instead.

Clover: new version of A. Note anytime the dirt comes into contact with water it dissolves instantly but some solution always remains. So what you really want to do is dilute that solution as much as possible. Maybe theres an equation for this or along the lines of but I haven’t taken fluids yet so.. what i will say is that the more number of times you fill and empty the better off you are. So maybe instead of filling the bottle up all the way, you should fill it some optimal fraction so that you fill and empty the bottle more times. Perhaps you should even change the fraction, slowly increasing or decreasing. My best guess is decreasing. This is assuming that the amount of solution that remains behind is always a constant. Note i’m also betting that in the official answer they probably set N= number of times the bottle is filled and emptied and S= amount of solution left behind each time.

Lets Continue.

“It is clear that nothing is to be gained, at any stage, by re-using the rinsings from an earlier stage, since this would only serve to increase the concentration of the residue. If a volume of water knR (kn is a numerical factor to be determined) is added during the nth cycle of operations, the amount of dirt remaining is reduced according to Dn= Dn-1R/(R+knR). Thus after p operations,

Dp/D0=II 1/(1+kn)

if kn is kept at a constant value, k, then the number of operations to use all the water is W/kR and so

D/D0 = (1+ k)^(-W/(kR))

thus

ln (D/D0) = –W/R ln(1+k)/k

The largest value of the right-hand side (=W/R) occurs when k=0, and thus the smallest value of D is given by D=D0^(-W/R) and is obtained yb using as little water as possible for each operation. It is clear from this result that no improvement results from trying any procedure other than keeping kn constant.”

-same citation.

To paraphrase the “I’m on a boat” song..

This is as Real as it gets!

So…I’m going to say that out of 50 points we probably would have gotten …

A: if the teacher has a sense of humor: 45/50, if not: 0/50

2: 4/50

III: Kicked out of the University of Bristol

Clover: 35/50

Please appreciate the fact that I wrote out my answers before looking at the book’s answer and did not go back and change a word despite the grand temptation p.s.

Your turn

Problem 60: You have no mackintosh or umbrella, and have to make a journey ton foot in steadily falling rain. FI you run, the journey will not take so long, but you may intercept more rain. Taking as your criterion the necessity to minimize the number of rain drops that strike you and assuming that the rain falls steadily and vertically at 10 m/s construct a theory that enables you to decide the best speed at which to run. Mention any short comings of the theory which occur to you.

I’ll post the answer after receiving 4 ideas from you my beloved audience.

Need more insanity?

http://www.physics.harvard.edu/academics/undergrad/problems.html

A professor, David Morin, at Harvard used to post one physics problem each week. They’re all still up with the solutions but the last one was posted May 31 2004. Happy Hunting.

Oh and this post is dedicated to Dr. Rassoul for recommending the book to me when I came to FIT to visit before applying. (7 PREPOSITIONS in one sentence!) and of course props to Raymond for welcoming us to reality.