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प्रश्न
How many photons of frequency 1014 Hz will make up 19.86 J of energy?
उत्तर
E = 19.86 J
v = 1014 Hz
E = nhv
n = `"E"/"hv"`
= `19.86/(6.626 xx 10^-34 xx 10^14)`
= 2.997 × 1020
Number of Photons N = 3 × 1020
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