A red laser pointer emits light with a wavelength of 730nm. What is the frequency of this light?
What is the energy of 1 mole of these photons?
frequency=speed of light / wavelength.
so frequency = 2.9979 x 10^8 m/s divided by 730 x 10^-9 m
so frequency = 4.107 x 10^14 / second
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