# Search results

1. ### Haunted House Door

Hi all. I am in the middle of a ridig body rotation problem. Anyways, I have x double dot = sin(x) and i need to find what x dot is. x is a function of time 't' and I just have no idea how to get it. so it is d^2x(t)/dt^2=sin(x(t)) where x(t) is a function and i need to find dx(t)/dt...
2. ### A few questions on Quantum mechanics

Hi all, I am doing quantum stuff in my physics class right now and have a few question that I would like to know the answers to... 1) A partical has wave proporties that relate to the probability of where it exists. I guess my question is how do particals move? Like can they exist anywhere...
3. ### UCLA or Berkeley for undergrad physics?

Thank for the opinions guys... and ucla does have hot girls
4. ### Magnet Broken in Half

Hmm, I think it is half as magnetic but you must prove it. Your professor might just mean that your arguement is invalid but the conclusion is true.
5. ### UCLA or Berkeley for undergrad physics?

Hello all, I have to decide between UCLA and berkeley for undergrad physics. I would rather go to UCLA for social reasons, but i know berkeley is a great school for physics(im sure UCLA isnt half bad either). My question is how important is the school for undergrad. i know for grad school the...
6. ### Where is the beginning?

I would stay start with mechanics, then E and M, then modern physics. You should leave some calculus. If you want to jump into something really interesting that you might beable to grasp right now, read about special relativity.
7. ### Sound frequency

Sorry man, I was incorrect on Ochtaves but the way you explained the speed thing was unclear.
8. ### Sound frequency

None of this is true... If a sound wave has wavelength L and another has wavelength L/2 in the same room then they still will move at the same speed. The one with L/2 will have twice as high of a frequency. speed of sound = wavelength times frequency... and the speed of sound is pretty much...
9. ### What's the optimum air pressure for sound waves?

flow of sound waves would be messured as the velocity of the sound.
10. ### Need some help with Applications and Problem Solving .

It needs to be 12 X 8 which has an area of 96 cm. We will call the sides of the frame 'a' and we know that all the sides have a length of 'a'. the area of the area inclosed by the frame is just a*a. So we need to take the total area enclosed (a^2) then subtract the area of the picture inside...
11. ### Can some help me explain what they are trying to say

Find where centripetal acceleration = g. so a=w^2 * r. where w is angular velosity and r is radius of earth. make g=w^2*r, solve for w. then see that the ratio of w is to the actual angular velosity of earth. What is actually happening at this point is the earth ( and therefore you) is...
12. ### Simple Question?

A) W=F dot x... ramp is 7m long and the mover is pushing in the same direction as the ramp with 680N. W= 680N * 7.0m = 4800j. B) What is the machine?
13. ### Why not a Left Hand Rule?

I would think that with a negative partical, the vector is pointing in the opposite direction, so you really still need to apply the right hand rule.
14. ### Rolling ball physics in 2D, how?

If I were you, I would work in energy. Ball starts out with some energy 'E'. This will be only potential grav energy if it starts at rest on top of the ramp. Could be both is you have an initial speed. Anyways, you can just sent up energy equations. This will make it easy to include Kinetic...