The photoelectric threshold frequency of metal is ν . When the light of frequency 4ν is incident on the metal, the maximum kinetic energy of the emitted photoelectrons is

Question

The photoelectric threshold frequency of metal is ν . When the light of frequency 4ν is incident on the metal, the maximum kinetic energy of the emitted photoelectrons is (A) 4hν (B) 3hν (C) 5hν (D) (5/2)hν

Tardigrade Admin · Accepted Answer

From Einstein's photoelectric equation the maximum kinetic energy of photoelectrons emitted from the metal surface is given by

E_{k} = h ν_{1} - W

Where

W

is the work function of the metal.
Given,

W = h ν

and

ν_{1} = 4 ν

∴ E_{k} = 4 h ν - h ν = 3 h ν

Q. The photoelectric threshold frequency of metal is $ν$ . When the light of frequency $4 ν$ is incident on the metal, the maximum kinetic energy of the emitted photoelectrons is

$4 h ν$

$3 h ν$

$5 h ν$

$\frac{5}{2} h ν$

From Einstein's photoelectric equation the maximum kinetic energy of photoelectrons emitted from the metal surface is given by
$E_{k} = h ν_{1} - W$
Where $W$ is the work function of the metal.
Given, $W = h ν$ and $ν_{1} = 4 ν$
$∴ E_{k} = 4 h ν - h ν = 3 h ν$

Q. The photoelectric threshold frequency of metal is ν . When the light of frequency 4ν is incident on the metal, the maximum kinetic energy of the emitted photoelectrons is

4hν

3hν

5hν

25​hν