Is photoelectric emission instantaneous?

The Photoelectric effect is an instantaneous phenomenon. There is no time delay between the incidence of light and emission of photoelectrons. The energy of emitted photoelectrons is directly proportional to the frequency of incident light.

Are electrons emitted instantaneously?

Electrons are emitted from the surface almost instantaneously, even at low light intensities. When a photoelectric effect is observed, the number of electrons ejected is proportional to the intensity of the incident light. The maximum kinetic energy of the photoelectrons increases with higher frequency light.

Why is photoelectron emitted instantaneously?

According to quantum mechanics The energy is transmitted by photon to electrons by the collision between the two. Only those photons can eject electrons which have energy more than or equal to a minimum required energy (threshold energy). Since energy is transferred in a lump, the ejection is instantaneous.

Is there a time delay with the photoelectric effect?

There is no time lag between the incidence of photons and emission of photoelectrons in photoelectric effect. No. There is no time lag between the incidence of photons and emission of photoelectrons in photoelectric effect. This is one of the major drawbacks of wave theory.

What are experimental observations of photoelectric effect?

Variation of photoelectric current with intensity of radiation absorbed: When the values of photoelectric current were plotted against the different values for intensity of light, it was observed to be a straight line passing through the origin.

How do you demonstrate photoelectric emission experimentally?

It is quite easy to demonstrate the photoelectric effect with an electroscope and a short wave UV-C lamp. By placing a negative charge on the electroscope, and shining the short wave UV light on top, it will discharge.

Does photocurrent depend on frequency?

does not depend on the frequency of incident light but depends on the intensity of the incident light.

How does intensity affect photocurrent?

A higher intensity of radiation produces a higher value of photocurrent. For the negative potential difference, as the absolute value of the potential difference increases, the value of the photocurrent decreases and becomes zero at the stopping potential.

How did Einstein explain the observed fact of photoelectric effect?

Since light is bundled up into photons, Einstein theorized that when a photon falls on the surface of a metal, the entire photon’s energy is transferred to the electron. A part of this energy is used to remove the electron from the metal atom’s grasp and the rest is given to the ejected electron as kinetic energy.

Why is there no delay in the photoelectric effect?

The incident light energy is distributed uniformly over the illuminated surface. The time required for an area the size of an atom to acquire enough energy to allow the emission of electron can be calculated from the intensity of the incident radiation. No time lag has ever been observed.

What is Hertz and Lenard’s observation?

Hertz and Lenards observation In 1887 by Heinrich Hertz observed that when light falls on a metal surface, some electrons near the surface absorb enough energy from the incident radiation to overcome the attraction of the positive ions in the material of the surface.

What is saturation current class 12?

The maximum value of the photoelectric current is called the saturation current. Saturation current implies that all the photoelectrons emitted by the emitter are immediately collected by the anode.