WEBVTT
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This is College Physics Answers
with Shaun Dychko.
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The energy of a photon is given
by equation [29.13]
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which is Planck's constant
times the frequency
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and we are told the frequency is
100 megahertz.
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So we go 100 times 10 to the 6 hertz
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multiplied by Planck's constantâ€”
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4.14 times 10 to the minus
15 electron volt secondsâ€”
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giving an energy of 4.14 times 10 to the
minus 7 electron volts.
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And then we compare that with
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representative energies for
sub-microscopic effects
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and we see that the
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binding energy of a weakly bound molecule
is about 1 electron volt.
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And so we take this photon energy,
divide it by that
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and we get 4 times 10 to the minus 7.
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So the photon energy is about 4 times
10 to the minus 7 times smaller
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than typical molecular binding energies.