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Question
If the total energy of radiation of frequency 1014 Hz is 6.63 J, calculate the number of photons in the radiation. (Planck’s constant = 6.63 x 10–34 J.s.)
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Solution
Given: E = 6.63 J, v = 1014 Hz, h = 6.63 x 10–34 Js.
`n = E/(hv) `
` =6.63/(6.63xx10^(-34) xx 10^(14))`
` =6.63/(6.63xx10^(-20))`
`n = 1/10^(-20)`
`n = 10^20`
The number of photons emitted in the radiation are 1020.
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