Question

The surface of a metal is illuminated with the light of 400 nm. The kinetic energy of the ejected photoelectrons was found to be 1.68 eV. The work function of the metal is (hc = 1240 eV. nm)–

• A. 3.09 eV
• B. 1.41 eV
• C. 1.51 eV
• D. 1.68 Ev

Answer 1

Answer: (B)

1.41 eV

Answer 2

=

⇒ φ =

= $\frac { 1240 } { 400 } - 1.68$ = 1.41 eV