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Question
The energy of a photon of wavelength 663 nm is ______.
Options
6.64 × 10-20 J
5.18 × 10-19 J
3.0 × 10-19 J
2.0 × 10-20 J
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Solution
The energy of a photon of wavelength 663 nm is 3.0 × 10-19 J.
Explanation:
The energy of a photon of wavelength 663 nm can be calculated using the formula `E = (hc)/lambda`, where E is the energy of the photon, h is the Planck's constant, c is the speed of light in vacuum and λ is the wavelength of the photon.
Plugging in the value, we get,
E = `((6.62 xx 10^-34 xx 3 xx 10^8))/(663 xx 10^-9)`
E = `3 xx 10^-19` J
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