Recent content by DANIELLYMA

r is the radius of the source, how do I take into account the the 3d distance from the screen?

oops thanks for pointing out the typo but I still don't understand what power has to do with this problem.

I'm having problems doing the problem below. The equation in the hint is: I = Ps/(4*PI*r^2) which I have not clue how it relates to this question except for that it's an equation for intensity. I know that there will be a image produced a distance d behind the mirror, so there will be another...

Really hard Volume Question. URGENT! Can someone help me with this question? I don't know where to begin. I don't want the answers, just hints in the right direction *edit* can a mod please fix the topic title? It's supposed to read 'Really hard Volume Question. URGENT!' << Done. >>...

what happened to the r1^3/r2 term?

yea that's right I think, Vr2 would equal to kQ/r but I'm also stumped on how it is simplied to the final answer.

Edit: I reuploaded the picture, thanks for your replies

Hi I think I figured it but I'm not sure. Here's the problem: How Much Work In Fig. 25-34, how much work is required to bring the charge of +5q in from infinity along the dashed line and place it as shown near the two fixed charges +4q and –2q? Take distance d = 1.40 cm and charge q = 1.6 ×...

A 75 kg man is sitting in his car at rest at the stoplight. He is rear-ended by another car and is accelerated to 3.0 m/s in 0.2s. What is the impulse on the man and his car? I found the impuse on the man which was: I = m(change v) = 75(3.0 -0) = 225 Ns I found the Net force on the...

My teacher told me it wasn't in equilibrium since there is a torque.

I don't undestand what you mean. The beam is not in equilibrium, and I know torque caused by the wall is zero, but I was wondering what's the direction of the force exerted by the wall.

Here's an image of the problem I trying to do. http://img339.imageshack.us/img339/1765/torquequestionqv0.th.gif I'm wondering if there is a force exerted by the wall on the beam, and if so in which direction? I think it's pointed upward to the right, but I'm not too sure. Any help...

Does anyone have a solution?

I think it can be figured out because as I previously posted, my teacher hinted at using the speed of sound, speed of light, and a stop watch.

Thanks for the answer, but is there a way to estimate the speed of the jet?