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If the total energy of radiation of frequency 1014 Hz is 6.63 J, Calculate the number of photons in the radiation.

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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. 

Sum
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Solution

Given:

E = 6.63 J, ν = 1014 Hz,
We know, h = 6.63 × 10–34 Js.

To find: Number of photons (n)   

Formula: n = `"E"/"hv"`

Calculation:

Using formula,

n = `6.63/(6.63 xx 10^-34 xx 10^14)`

∴ n = 1020 

The number of photons emitted in the radiation is 1020.  

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Chapter 14: Dual Nature Of Radiation And Matter - Short Answer I

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SCERT Maharashtra Physics [English] Standard 12 Maharashtra State Board
Chapter 14 Dual Nature Of Radiation And Matter
Short Answer I | Q 5

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