When light of wavelength λ is incident on a metal with a work function of hc/λ_0 , the photoelectric effect will occur only if

Concepts Of Physics MCQ Edition [Volume 2]

Exam: Concepts Of Physics MCQ Edition [Volume 2]
Subject: Physics
Chapter: Photoelectric Effect and Wave–Particle Duality

Concepts Of Physics MCQ Edition [Volume 2] · Physics · Photoelectric Effect and Wave–Particle Duality

When light of wavelength λ is incident on a metal with a work...

When light of wavelength

\lambda

is incident on a metal with a work function of

hc/\lambda_0

, the photoelectric effect will occur only if

Options

A $\lambda \leq \lambda_0$
B $\lambda < \lambda_0/2$
C $\lambda \geq 2\lambda_0$
D $\lambda \geq \lambda_0$

Correct answer

A. $\lambda \leq \lambda_0$

Step-by-step solution

For the photoelectric effect to occur, the energy of the incident photon must be greater than or equal to the work function of the metal.

The energy of the incident photon is

E = \dfrac{hc}{\lambda}

.

The work function of the metal is

\Phi = \dfrac{hc}{\lambda_0}

.

The condition for photoelectric emission is

E \geq \Phi

\dfrac{hc}{\lambda} \geq \dfrac{hc}{\lambda_0}

\lambda \leq \lambda_0

Practice Photoelectric Effect and Wave–Particle Duality on Quantrex Academy →

More from Photoelectric Effect and Wave–Particle Duality