A source `S_(1)` is producing `10^(15)` photons/s of wavelength `5000 Å` Another source `S_(2)` is producing `1.02 xx 10^(15)` photons per second of wavelength `5100 Å`. Then `("power of" `S_(2))/("power of" S_(1))` is equal to

Options

A. 1
B. 1.02
C. 1.04
D. 0.98

Answer

A

Explanation

Energy emitted / sec by `S_1,P_1 = n_1 (hc)/(lamda)`
energy emitted /sec by `S_2,P_2 =n_2 (hc)/(lamda_2)`
`therefore P_2/P_1 = n_2/n_1 .lamda_1/lamda_2 = (1.02 xx 10^15)/(10^15) . (5000)/(5100) = 1.0`