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!?
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...
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 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 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...