Ps−Power of source
Ps=nλhc;n = no. of photons emitted/s
⇒n∝λ⇒n1n2=1/500
JEE Main 2020 — Physics Electromagnetism
Two sources of light emit X-rays of wavelength 1 nm and visible light of wavelength 500 nm, respectively. Both the sources emit light of the same power 200 W. The ratio of the number density of photons of X-rays to the number density of photons of the visible light of the given wavelengths is:
Held on 3 Sept 2020 · Verified 6 Jul 2026.
5001
250
2501
500
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