Recent content by phy124

Oh... *sigh* Thank you for your assistance BvU, it was much appreciated!

But then for the outside wouldn't that mean that \frac{1}{\rho}\left({\frac{\partial (\rho A_{\phi})}{\partial \rho}}\right)\hat{z}=\frac{1}{\rho}\left({\frac{\partial (\rho\frac{ \mu_0 n I R^2}{2 \rho})}{\partial \rho}}\right)\hat{z}=\frac{1}{\rho}\left({\frac{\partial (\frac{ \mu_0 n I...

Sorry I don't think I'm following, I'm still not sure what I'm supposed to have for A_{\phi} then. I'm thinking that I need to get \mu_0 n I \hat{z} out of this as the result but I've tried many different things for A_{\phi} with no progress. What should the value of A_{\phi} be please. Ugh...

Ok thank you. So then do I write: A_{\phi} = \frac{\mu_0nIR^2}{2\rho}=\frac{\mu_0nI(\rho^2 + z^2)}{2\rho} Then after simplification as all other terms are zero \bigtriangledown \times A = -\frac{\partial A_{\phi}}{\partial z}\hat{\rho}+\frac{1}{\rho}\left(\frac{\partial (\rho...

Homework Statement / Homework Equations[/B] I was looking at Example 5.12 in Griffiths (http://screencast.com/t/gGrZEPBpk0) and I can't manage to work out how to verify that the curl of the vector potential, A, is equal to the magnetic field, B. I believe my problem lies in confusion about how...

Ah I see, thank you for your insight, you were very helpful. I'll be sure to come back here if I have any problems in the future ;)

Thank you tiny tim. Yes well here lies the problem, the cart doesn't have brakes and I'm pretty sure that friction acts in the opposite direction to that of the way which the wheels are moving, so it is in the same direction as the carts movement and thus making Fr = Wsinθ wrong?

Homework Statement Would constant velocity down a slope be achieved by a cart, by having the frictional force equal to that of Wsinθ (Where W is the weight force and θ is the angle between the slope and the horizontal). Homework Equations/The Attempt at a Solution For example if θ...