Answer:
2.6 * 10^21 photons
Explanation:
First we obtain the energy of one photon.
The energy of one photon = hf
h= Planks constant = 6.6 * 10^-34 Js
f = frequency of the radiation = 7.5 X 10^14 Hz
E = 6.6 * 10^-34 * 7.5 X 10^14
E= 49.5 * 10^-20 J
Number of photons = Total energy/ energy of one photon
Total energy = 1300 J
Number of photons = 1300/49.5 * 10^-20
Number of photons = 2.6 * 10^21 photons
