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?
-
A.
1.48ev -
B.
2.21ev -
C.
4.42ev -
D.
5.75ev -
E.
11.51ev
Correct Answer: Option B
Explanation
K.E = (frac{1}{2})mv2
E – W = 6.86 – 4.65
= 2.21ev