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thank you!

That makes sense, I guess the thing that is throwing me off is the "time-average". Intensity = time average of S I = <S> I= (1/2)*c*epsilon not*Emax^2 Can I say then that magnitude of I = magnitude of S or would I have to say magnitude of I = (1/2)*c*epsilon not*Emax^2 = (1/2) * S

General question: Is the magnitude of the poynting vector equal to the intensity of an electromagnetic wave? I know that I= average S which makes me think that I cannot simply assume that that their magnitudes are equal!?

i don't! :( All I have is the natural frequency in rad/sec.

Homework Statement if i know the natural frequency of a system, how can I generate a resonance curve for the system in terms of frequency vs amplitude. The Attempt at a Solution I know it will have one peak, like a bell curve and the max will be the natural frequency, but i don't...

[b]1. The problem statement If i generate a list of 300 random numbers in excel, each number between 1-50 for example, and i plot the frequency that each number comes in a histogram, how can i tell, looking at the histogram, if the numbers are really random? is there a certain distribution...

This is not really a homework question but a more general plea for an explenation from someone! :) In x-ray diffraction, you get a graph with different peaks that are particular to the composition of your sample. But, why are some peaks are of higher intesities then others? What is it about...

What is impurity doping? Can somebody please explain it?

Thanks again! :) :) :)

Thank you so much! oh ok, so it would just be I(3)+I(2)=I(1) right?

Homework Statement I need to find the current equation for the junction in node a in the following circuit: http://i749.photobucket.com/albums/xx137/abcdmichelle/gjgjhg.jpg Homework Equations Current in = Current out so I(in)=I(out) The Attempt at a Solution The arrows in the...

Homework Statement For the circuit in the figure below, V = 3.56 V and R = 2.04 Ω. Find the potential difference between points a and b. This is the link to the figure: http://i749.photobucket.com/albums/xx137/abcdmichelle/physics/26-62alt1.gif Homework Equations V=IR The Attempt...

Thank you so so so much! What great help!

Thank you Hellabyte! :) If I find V, then I know how to find E. So, V=Work/charge V=(0.5mv^2)/q thus V=(0.5MS^2)/Q Is this correct? I think it is, and from here I know how to do all the problem...assuming it is correct!?

Homework Statement A parallel plate capacitor has two conducting plates separated by a vacuum. The distance is D and the area of each plate is A. An alpha particle with mass M and charge Q is placed on the positively-charged plate, between the plates. It shoots through a small hole in the...

Thank you very very much Doc Al! This makes so much sense!

Thank you Doc Al! So for r=17, if R is the outer radius of the sheath, then Q=rho(length)piR^2, so E=(rho(length)piR^2)/(2pi(length)r(epsilon_o), thus E=(rhoR^2)/(2r(epsilon_o)) is that correct, where i would use r=17 and R=15?? I still don't know how I would figure out E for r=12, the...

Homework Statement A non-conducting, infinitely long, cylindrical sheath has inner radius r=10 m, outer radius r=15 m and a uniform charge density of 9 nC/m^3 spread throughout the sheath. Magnitude of electric field at r=5, r=12, r=17? Homework Equations Q=rho(Volume) and phi=EA...