Hello all.
I'm trying to figure out how to determine the correct sign of paths and surfaces defined for calculating quantities in electromagnetic problems.
For example, say there's a wire in the shape of a rectangular prism along the z-axis with some current density, \vec{J} .
Then the...
Okefenokee,
In the past few months I've been covering more material and encountered some of what you've written above, but in textbooks.
I just wish I had read your response sooner! I would would have saved some time. :)
I know it's been a while since I posted but rest-assured (:wink:) that I read your responses and learned from them.
I'm still don't have a concrete understanding of the physical effect of the capacitors aside from the conceptual description you provided berkeman, but I suspect that this will...
Hi Everyone.
I actually had two distinct questions relating to circuit analysis and design. The first is theoretical and the second is a question about what I've observed on other circuits.
I'm reading some undergraduate EE books (I'm an EE student in Canada) and I've gotten to the point where...
*SLAPS HEAD*
Thanks Doc Al. This is the second time that you've helped me; I'm really grateful.
That's a testament to the importance of not rounding too early.
Thanks for the reply Doc Al :)
If you assume my FBD is correct, than it follows that the horizontal component of tension is equal to the electrical force.
Then: Fe = T \cdot cos(89^{\circ{}}) = 5.13 \times 10^{-5} N
Which isn't correct.
EDIT: I should also mention that the listed...
Homework Statement
A ping-pong ball of mass 3.0 \times 10^{-15} is hanging from a light thread 1.0 m long, between two vertical parallel plates 10 cm apart, as shown. When the potential difference across the plates is 420 V, the ball comes to equilibrium 1.0 cm to one side of its original...
Doc Al! Thank you so much for that help. It was exactly what I needed: it gave strong hints, and forced me to think.
In case anyone is interested:
0 = 110 v_c + 10(v_c + 5)
v_c \approx -0.417 m/s
In the frame of reference of the boat...
0 = 100v_c + 10(v_c + 5)
v_c = -5/12 m/s
Get...
When you say after the throw, do you mean after the first ball is thrown (before which, the canoe is stationary), or after the second ball is thrown by the girl on the moving canoe?
Thanks Doc Al. If I'm not mistaken, that leads me to this answer:
\vec{p} = (-5/11)(110) = \vec{p \prime} = 100v_c + 10(-5/11 + 5)
-50 = 100v_c + 500/11
v_c = -0.9545
Which is the same as my previous attempt. I think that makes sense, as I've just switched frames of reference. What am...
[SOLVED] Conservation of Momentum and Thrown Objects
As part of our physics class, we've been given lots of problems typically solved by taking into account the law of conservation of momentum. I've had little-to-no trouble solving them, but one problem in particular is driving me nuts...
I hope this is in the right place.
I'm in grade 12, and I've been given an assignment involving complex numbers.
The question reads:
Use De Moivre's Theorum to verify the identities:
cos(2\theta) = cos^2\theta - sin^2\theta
sin(2\theta) = 2sin\theta cos\theta
I've tried something like this...