The energy flux of the sunlight reaching the surface of the earth is `1.388xx10^(3) W m^(-2)`. How many photons (nearly) per square meter are incident on the earth per second? Assume that the photonsin the sunlight have an average wavelength of 550 nm.

Explanation

`n=P/E=P/(hc//lambda)=(Plambda)/(hc)=((1.388xx10^(3))xx550xx10^(-9))/((6.63xx10^(-34))xx(3xx10^(8)))=3.84xx10^(21)"photons"//m^(2)-s`