All Questions
Tagged with intensity electromagnetism
10 questions
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The relation between intensity and electric field
For a plane wave of the form $E=E_0 \cos(\omega t- k z)$, the intensity is $I=\frac{1}{2}c\epsilon_0E_0^2$. This can be derived by noting that $I=\langle S\rangle$, where $\langle
\,\rangle$ denotes ...
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Why is the intensity of a beam of light the squared magnitude of the phasor and not just the squared magnitude of the real part?
I'm learning about phasors and light intensity and there are two conflicting things I've been told that I can't reconcile.
Firstly I've been told that a phasor $e^{-ikz+i\phi}$ is a mathematical way ...
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Why the intensity of a wave is $ \Psi \Psi^*$?
In here at the bottom, it says the intensity of a wave is the wave phasor times it's conjucate
$$ I(x) = \Psi \Psi^* = |\Psi |^2$$
But when I compute the intensity of an electromagnetic wave in c.g.s, ...
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Poynting vector and intensity of a signal
Given a plane monochromatic electromagnetic wave propagating in $x$ direction, with associated electric and magnetic fields of the form:
$\overrightarrow{E}(x,t)=\overrightarrow{E_0}\cos(kx-\omega t), ...
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Parabolic mirrors used in pair to produce much higher intensity light beam ready for transmission?
If a parabolic mirror is used to concentrate sunlight approximately to a focus point why can't an another smaller parabolic mirror be used to reparalelise the beams that are leaving the focal point ...
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Calculate the amplitude and the frequency of the magnetic force acting on an electron
A free electron is located in the electromagnetic field of a laser with a given wavelength and intensity.
Is it possible to calculate the amplitude and frequency of the magnetic force that is acting ...
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Confused on intensity of light
If light behaves both as particle and wave at the same time, does it mean intensity (energy) of light depends on the square of its amplitude and at the same time energy of photons doesn't depend on ...
- 1,691
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Intensity at $\theta = 0$ in slit diffraction
From the explanation on diffraction at http://web.mit.edu/viz/EM/visualizations/coursenotes/modules/guide14.pdf
$$I = I_0\left [ \frac{\sin(\beta/2)}{\beta/2} \right ]^2=I_0\left [ \frac{\sin(\pi a \...
- 2,637
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How to explain the relationship between wave's amplitude and intensity?
I have the following statement which I don't know how to explain:
Suppose I have 2 identical monochromatic waves (same intensity and phase) shooting into the same receiver. If each wave's intensity ...
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Relation between intensity of light and amplitude of electric field?
A question in my textbook involve finding the electric field amplitude at a point in space given the intensity of light. It uses the following equation to solve it:
$$I=\frac{1}{2}\epsilon_{0}|E|^2c$$
...
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