The light rays having photons of energy 4.2 eV are falling on a metal surface having a work function of 2.2 eV. The stopping potential of the surface is :

Question

The light rays having photons of energy 4.2 eV are falling on a metal surface having a work function of 2.2 eV. The stopping potential of the surface is : (A) 2 eV (B) 2 V (C) 1.1 V (D) 6.4 V

Tardigrade Admin · Accepted Answer

KE = hv -φ eV V 0= h v-φ eV 0=4.2 eV -2.2 eV ⇒ V 0=2 Volts

Q. The light rays having photons of energy $4.2 e V$ are falling on a metal surface having a work function of $2.2 e V$ . The stopping potential of the surface is :

$2 e V$

$2 V$

$1.1 V$

$6.4 V$

$K E = h v - ϕ$
$e V V_{0} = h v - ϕ$
$e V_{0} = 4.2 e V - 2.2 e V$
$\Rightarrow V_{0} = 2$ Volts

Q. The light rays having photons of energy 4.2eV are falling on a metal surface having a work function of 2.2eV. The stopping potential of the surface is :

2eV

2V

1.1V

6.4V