The surface of the 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 metal is :

1.51 eV

No worries! We‘ve got your back. Try BYJU‘S free classes today!

1.42 eV

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

3.0 eV

No worries! We‘ve got your back. Try BYJU‘S free classes today!

1.68 eV

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is B 1.42 eV
As we know,

$ϕ_{0} = \frac{h c}{λ} - E_{k}$ (Einstein's equation)

$= \frac{1240 e V n m}{400 n m} - 1.68 e V$

$= 3.1 - 1.68 = 1.42 e V$

Suggest Corrections

Similar questions

Q. The surface of a metal is illuminated with the light of

400 n m

. The kinetic energy of the ejected photoelectrons was found to be 1.68

e V

. The work function of the metal is :

(

h c = 1240

e V . n m

)

A light source of wavelenght $^{'} λ^{'}$ illuminates on a metal surface, a photoelectron of Kinetic energy $1 e V$ is emitted. The another light source of wavelength $\frac{λ}{3}$ ejects photo electron from the same metal surface with Kinetic energy is $4 e V$ , the value of work function is