Question

The wavelength of an electromagnetic radiation is 662.5 nm. What is its energy in Joules ?

Answer 1

Answer:

Erg is the dimension of energy in CGS (centimeter-gram-second) system of units.

Therefore, 1erg=10−7joules.

Now, the energy of photon is 3 x 10−19J.

Using E=λh×c​,

Wavelength (nm)=3×10−19J3×108m/s×6.626×10−34​Js=662nm.