# Why threshold frequency is necessary for photoelectric effect?

Last Update: April 20, 2022

This is a question our experts keep getting from time to time. Now, we have got the complete detailed explanation and answer for everyone, who is interested!

The photoelectric effect is a phenomenon that occurs when light shined onto a metal surface causes the ejection of electrons from that metal. ... This minimum frequency needed to cause electron ejection is referred to as the threshold frequency.

## What is important about the threshold frequency?

The threshold frequency of a metal refers to the frequency of light that will cause an electron to dislodge from that metal. ... Light at the threshold frequency will dislodge the electron with no kinetic energy. Light above the threshold frequency will eject an electron with some kinetic energy.

## What is the threshold frequency for the photoelectric effect?

The photoelectric threshold frequency, symbolized by the Greek letter nu with subscript zero, ν0, is that frequency at which the effect is barely possible; it is given by the ratio of the work function symbolized by the Greek letter psi, ψ, to Planck's constant (ν0 =…

## What is threshold frequency and work function in photoelectric effect?

Threshold Frequency: The threshold frequency is that minimum frequency of light below which the photoelectrons do not emit. Work function: The least energy which can eject the electrons from the surface of the metal.

## How does frequency affect photoelectric effect?

In the photoelectric effect, electrons are ejected by a metal plate when hit by photons of electromagnetic radiation. ... The shorter the wavelength (the higher the frequency), the more the energy of the photon.

## Photoelectric Effect, Work Function, Threshold Frequency, Wavelength, Speed & Kinetic Energy, Electr

18 related questions found

### What is the principle of photoelectric effect?

The photoelectric effect is the process whereby the energy from electromagnetic radiation, such as visible light, gamma radiation or other, hits an atomic electron whereby the energy of the radiation is transferred in its entirety to the electron causing the electron to be ejected from the atom.

### What is Einstein photoelectric equation?

: an equation in physics giving the kinetic energy of a photoelectron emitted from a metal as a result of the absorption of a radiation quantum: Ek=hν−ω where Ek is the kinetic energy of the photoelectron, h is the Planck constant, ν is the frequency associated with the radiation quantum, and ω the work function of the ...

### What is difference between threshold frequency and work function?

The minimum frequency of the incident light at which the emission of the electrons starts is called the threshold frequency. It is different for different materials. The minimum energy necessary to initiate the photoelectric effect from the metal surface is called the work function.

### What happens threshold frequency?

The photoelectric effect is a phenomenon that occurs when light shined onto a metal surface causes the ejection of electrons from that metal. ... This minimum frequency needed to cause electron ejection is referred to as the threshold frequency.

### What is the threshold frequency?

: the minimum frequency of radiation that will produce a photoelectric effect.

### What is photoelectric effect give an example?

photoelectric effect, phenomenon in which electrically charged particles are released from or within a material when it absorbs electromagnetic radiation. The effect is often defined as the ejection of electrons from a metal plate when light falls on it.

### What is threshold frequency and its formula?

Threshold frequency in photoelectric effect is the minimum frequency of electromagnetic radiation which is required for the phenomenon of photoelectric emission to occur from a metal surface. ... The formula of threshold frequency is W= hv0.

### Is threshold frequency same for all metals?

Different metals have different values of work function because of difference in their electronegativity. The frequency of the photon with energy equal to work function is called threshold frequency. The value of photocurrent depends on the intensity of the falling radiation.

### What happens if frequency is equal to threshold frequency?

Light with frequency equal to threshold frequency will eject the electron without any release of kinetic energy. If the frequency of light is more than the threshold frequency, kinetic energy is released with ejecting the electron.

### What is the threshold frequency of a photon?

Threshold frequency v0​ is the minimum frequency which a photon must possess to eject and electron from a metal.

### Does work function depend on frequency?

Depends upon the frequency of incident light. Hint: The different metals consist of different values of work function because of difference in their electronegativity behaviour. Therefore the work function is that amount of energy which is required to get an electron out of the metal plate without any kinetic energy.

### What is the difference between cutoff frequency and threshold frequency?

i) Cut-off or stopping potential is that minimum value of negative potential at anode which just stops the photo electric current. ii) The minimum frequency of light below which no photo electric emission will take place is known as threshold frequency.

### What is Einstein equation?

2. The mass of the nucleus is about 1 percent smaller than the mass of its individual protons and neutrons. This difference is called the mass defect. The mass defect arises from the energy released when the nucleons (protons and neutrons) bind together to form the nucleus.

### How did Einstein prove the photoelectric effect?

Light, Einstein said, is a beam of particles whose energies are related to their frequencies according to Planck's formula. When that beam is directed at a metal, the photons collide with the atoms. If a photon's frequency is sufficient to knock off an electron, the collision produces the photoelectric effect.

### Which metal is best for photoelectric effect?

So, among the given options, cesium has the lowest ionization potential and hence it is best suitable for photoelectric effect.

### What is the application of photoelectric effect in engineering studies?

The photoelectric effect is used in a plethora of other devices, including photocopiers, light meters and even electronicsl components such as photodiodes and phototransistors. The other fabulous application fo the photoelectric effect is scintillators.

### What is the threshold frequency of cesium?

The threshold frequency for caesium metal is 5.16×1014Hz.

### What is the formula of threshold energy?

Kmin = Kth = −Q MX + mx MX This equation is valid if the energies are much less than rest mass energies of the involved particles. In other words, the kinetic energy and momentum of particles can be treated classically, or non-relativistic.

### What is the formula of threshold wavelength?

The frequency of the light for which its energy is equal to the work function is called threshold frequency ν0. Therefore, ϕ=hν0. Let us use the relation between the frequency and the wavelength of light, i.e. ν=cλ. When the light wave has threshold frequency, its wavelength is called threshold wavelength (λ0).