Photoelectric Effect | MCQs

Explanation

The photoelectric effect does not occur if the frequency of the incident light is below the threshold frequency.

The threshold frequency is the minimum frequency required for the incident photons to have enough energy to eject electrons from the surface of the material.

If the frequency is below this value, no electrons are emitted, regardless of the light intensity.

Explanation

If the frequency of incident radiation in the photoelectric effect is increased beyond the threshold frequency, it will not affect the photoelectric current. 

Explanation

The reverse process of the photoelectric effect is the production of X-rays when electrons are decelerated.

In the photoelectric effect, light (photons) interacts with a material, causing electrons to be emitted.

Explanation

The maximum kinetic energy (K.E.) of photoelectrons depends on the frequency of the incident light, not its intensity. 

According to Einstein's photoelectric equation:

K.E. = hf - φ

where hf is the energy of the photon, which depends on its frequency (f).

Explanation

The phenomenon where light of suitable frequency falling on a metal surface ejects electrons is called the "photoelectric effect."

Explanation

The stopping potential is the voltage applied to the electrodes in a photoelectric effect experiment that just prevents the most energetic electrons from reaching the anode.

Since the kinetic energy of the ejected electrons is directly proportional to the frequency of the incident light (above the threshold frequency), a higher frequency light will result in more energetic electrons.

Therefore, the stopping potential, which is the voltage needed to completely stop these most energetic electrons, is also directly proportional to their energy. 

Explanation

The photoelectric effect occurs at energies less than 0.5 MeV.