Recent content by Vuldoraq

Thanks for the reply @fresh_42! I was quite surprised to see one after 11 years, but it's appreciated. Totally forgot this forum existed, will see if I can brush up on my physics and maths and get more involved.

Anyone have any ideas? Please say if I haven't explained myself properly.

Hi, Please could someone help me with the following? Sorry for the extra long post! Homework Statement a) Using the Maximum/Minimum principle, find the maximum and minimum points of the solution of the following mixed problem; u_t - c^2u_{xx} = 0, \ \ 0 < x < l, \ \ t>0 u(0,x) = x(x-l) \ \...

Looks good to me so far, I haven't checked the actual numbers but the principles are fine. Edit:Checked the numbers and they look fine too.

One of these equations are not correct for a capacitor with a dielectric. They should be, C=\frac{k\epsilon_{0}A}{A} By E_{0} do you mean electric field or permitivity of free space?

Your value of mu should always be less than one. I think you need to find the difference between the actual force at the bottom and the theoretical force at the bottom. Please could you post equations that would give the component of weight normal to the surface and the component of wieght...

What are D, T, A? I take it Fn is the normal force, Ff is the friction force and Vi is the initial velocity? Please could you show some of your working? You should obtain expressions involving trig. functions and the properties of your mass.

Oh, I see. Sorry, that is a badly worded question (or more likely I read it badly). I thought it meant it's being stretched four feet beyond it's elestic limit! My bad. Given that is true I think your answer is correct, at least in it's principle (Ihaven't checked the numerics).

Could you explain your limits of integration? The spring is either being stretched from 0 to 6 ft or from 2 to 6 ft, I don't see where you got 0 to 4 from.

Try drawing an overall diagram of the situation, then draw a free body diagram for the lower magnet. Is the table resting on a surface? Or is it suspended, being help in place by the two magnets? In either case there should only be three forces you need to take into account, and two of them...

Firstly how is F (the force) related to the extension (or compression) of an ideal spring?

The current and the magnetic field are always at right angles to each other. It is true that the magentic field flows in the same direction as the net current flow, but only in this special case. For emf see here: http://en.wikipedia.org/wiki/Electromotive_force Also try to post int...

Hi, Have you drawn a free body force diagram? Also we need to see your attempt at the solution before we can help you.

Hey CompuChip, Could I be really cheeky and ask another question :shy:? It is one of the follow ups to to the previous question, (b) Compute the occupancy of each energy level, for q = 6. Draw a graph of the occupancy as a function of the energy of the level. (You may wish to let the...

Your hand is providing all the work agianst gravity required to lift the book to it's new position. So the work your hand does is directly related to the change in potential energy. Can you see how?