The work function of a metal is 4.65ev and the metal is illuminated with a radiation of 6.86ev. What is the kinetic energy of the electrons ejected from the surface of the metal?
1.48ev
2.21ev
4.42ev
5.75ev
11.51ev
Correct answer is B
K.E = \(\frac{1}{2}\)mv2
E - W = 6.86 - 4.65
= 2.21ev