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hightechburrito
12-16-2000, 03:04 AM
I am currently cramming for my physics final on Monday, and there are a few subjects that are giving me a bit of trouble. These subjects are also conviniently what the final is heavily based on. The main ideas I am having trouble with are rotational dynamics and oscillations.

So I am turning to all the physics geniuses out there. If you have any helpful hints or links to good websites, please share them.

I thank you all in advance.

AxeElf
12-16-2000, 03:06 AM
Sounds like a good stripper might help at this point...

Smeghead
12-16-2000, 03:23 AM
Sorry. My physics posts are strictly limited to the purely theoretical. Took physics years ago and got through it by the skin of my teeth. In the semester on electricity and magnetism, it wasn't until I was studying for the final that I finally figured out what voltage is. I can handle concepts OK, but don't ask me to do the math. *Shudder*

Bob Scene
12-16-2000, 04:39 AM
Physics all boils down to either Newton's laws of motion and gravitation or Coulomb's law of electrical attraction/repulsion. Hope this helps!

ElvisL1ves
12-16-2000, 08:52 AM
Just remember 2 things, and the rest follows:

1. F = m a
2. You can't push a rope.

bibliophage
12-16-2000, 01:56 PM
Rotational physics is easy. Take the equations governing translational movement and substitute the rotational terms for the translational ones. Substitute angle for displacement
angular speed for translational speed
angular acceleration for translational acceleration
Moment of inertia (rotational inertia) for mass (translational inertia)
torque for force
time remains time
Energy remains energy
Power remains power

For example s=s0+v0t+½at2 becomes theta=theta0+omega0t+½alpha*t2
F=ma becomes tau=I*alpha
Work=integral of Force with respect to distance becomes W=integral of torque with respect to angle
K=½mv2 becomes K=½I*omega2

For kinetic energy, the first equation gives translational K.E., the second gives rotational K.E. Some objects, like a rolling ball, have both a the same time

This sort of substitution won't work for mixtures of translational and rotational terms. (Don't try it on tau= r×F )