Why is the sky blue?
Moreover, (iii) The amplitude of oscillation tends to a maximum when (iv) There is a small phase difference
approaches
209
between the light taken and the oscillation.
Now the instantaneous power radiated by an accelerating charge is
where is the instantaneous acceleratio oscillating dipole can be calculated by differentiating (4) twice to give
n of the charged body. 210 The power radiated by an
The mean value of
is 1/2 over a duration
, so the mean power is
Intensity is related to power by
Where A is the cross-sectional area. So
(7)
Blue light creates the greatest dipole moment amplitude (as it is closest to the natural frequency of
the atom) and it also has the highest frequency. The greatest the intensity of light scattered is the greatest in blue light.
value is found in blue light and so
We are going to use (7) to bring this full circle and improve on the first result of this essay:
.
209 Pain, H.J. ‘3 The Forced Oscillator.’ The Physics of Vibrations and Waves. Sixth ed. Chichester: Joh Sons Ltd., 2005. 53-74. Print. 210 Lipson, S. G., and H. Lipson. ‘5.3.1 Radiation Emitted by an accelerating charge.’Optical Physics. London: Cambridge U.P., 1969. 134-36. Print.
n Wiley &
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