Question

In photoelectric effect, the electrons are ejected from the metal surface, if the incident light has a certain maximum

• A. Wavelength
• B. Amplitude
• C. Frequency
• D. Angle of incidence

Answer 1

Answer: (A)

The photoelectron is emitted from a metal surface if the incident photon possesses a minimum required energy for photoemission, called as the work function.
Hence,
$\frac{hc}{\lambda }\ge \frac{hc}{{\lambda }_0}$
$\lambda \le {\lambda }_0$
Therefore, if the incident light does not have wavelength greater than the maximum wavelength ${\lambda }_0$ photoelectrons are emitted.