Question

A 7 eV photon is used to eject an electron from a metal. The most energetic ejected electron can be brought to rest by a 4-volt electrical potential. What is the work function of the metal?

Answer 1

work function = 3 eV

Step-by-step explanation:

given,

Energy of photon = 7 eV

electrical potential = 4 V

Work function = ?

using equation,

energy of photon = work function + qVs

work function = energy of photon - qVs

work function = 7 eV - 4 eV

work function = 3 eV

Hence, work function of the metal is equal to 3 eV