An AIR station is broadcasting the waves of wavelength `300 metres`. If the radiating power of the transmitter is `10 kW`, then the number of photons radiated per second is

Options

A. `1.5 xx 10^(25)`
B. `1.5 xx 10^(31)`
C. `1.5 xx 10^(33)`
D. `1.5 xx 10^(35)`

Answer

B

Explanation

Power = 10 kW `=10^4` J/s
Let n be the number of photons radiated/sec
`E = nh upsilon = (nhc)/(lambda)= 10 xx 10^3`
`therefore n = (10 xx 10^3 lambda)/(hc) = (10 xx 10^3 xx 300)/(6.66 xx 10^(-34) xx 3 xx 10^8)= 1.5 xx 10^(31)`