Q. 193.5( 41 Votes )

Work function of Sodium is 2.75eV. What will be KE of emitted electron when photon of energy 3.54eV is incident on the surface of sodium?

Answer :

In photoelectric effect, the energy of the incident photon must be equal to the sum of the metal's work function and the photoelectron kinetic energy:

E (photon)=KE (electron)+Φ

Where, E is total energy of incident light, KE is the kinetic energy of the photon and Φ is work function.

Now, E=K.E +ɸ

3.54eV = K.E + 2.70eV

K.E = 3.54-2.70 eV =0.84eV

So, the kinetic energy of emitted electron will be 0.84eV.

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.