In optical communication, compute the total energy if the energy of each photon is 1J and there are 1000 photons.

Concept:

\(\mathrm{Number \,of \, photons } = \frac{\mathrm{Total\, energy}}{\mathrm{Energy \,of \, one \, photon} }\)

From the above equation, total energy can be calculated as

\(\mathrm{Total\, energy} = \mathrm{Number \,of \, photons } × \mathrm{Energy \,of \, one \, photon}\)

Calculation:

Given;

The energy of each photon = 1J 

Number of photons  = 1000

Total energy = Number of photons × Energy of each photon = 1000 × 1 = 1000J

Additional InformationThe energy of a single photon is:

hν  or hω  = (h/2π )ω 

where h is Planck's constant: 6.626 x 10-34 Joule-sec. 

One photon of visible light contains energy in the order of  10^-19 Joules.