A mono chromatic source of light operating at 400 w emits \[8\times {{ – McqOptions

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1.	A mono chromatic source of light operating at 400 w emits \[8\times {{10}^{20}}\] photons per second, the wavelength of light is
A.	100nm
B.	200nm
C.	300nm
D.	400nm
Answer» E.

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