The precise shape of the surface of a metal will determine exactly where and how electrons move in the metal. Therefore, the threshold frequency and work function can vary .
Does threshold frequency depend on the metal?
Threshold frequency is the minimum frequency of incident light which can cause emission of photo-electrons from the metal surface. ... Threshold frequency of particular surface depends on nature of its material .
Is the threshold frequency different for different metals?
Threshold frequency and work function
Different metals have different work functions . This means it is easier to remove electrons from some metals than others. In turn, this means that the minimum frequency of photon needed to remove an electron from one metal can be lower than for another metal.
Is the threshold wavelength the same for all metals?
The alkali metals (sodium, potassium, and cesium) all had one threshold wavelength , and the other metals (copper, silver, gold, platinum) had a different threshold wavelength.
Is the work function the same for all metals?
Is different for different metals. ... 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.
How do you find the threshold frequency of a metal?
f = W/h where h is planck’s constant. Therefore if we know the work fucntion we can work out the threshold frequency but don’t forget to convert 3eV into J. 1eV = 1.6 x 10^{-19} J.
What does the threshold frequency depend on?
how does the threshold frequency depend on intensity of light in photoelectric effect? so, threshold frequency is property f the object not the light. so, threshold frequency of metal does not define the intensity of the light. Yes, for light itself, the intensity is more if frequency is more.
Is threshold frequency and work function the same?
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.
Why is the work function different for different metals?
Different metals have different values of work function because of difference in their electronegativity . The least electronegative (or most electropositive) metal would let go of its valence electron very easily compared to those metals with higher values of electronegativity.
Why is frequency greater than threshold frequency?
If the frequency is equal to or higher than the threshold frequency, electrons will be ejected . As the frequency increases beyond the threshold, the ejected electrons simply move faster.
What is threshold wavelength and work threshold frequency?
We know that the threshold frequency is the minimum frequency of the incident photon required for removing an electron from the metal surface . That is the energy of this photon should be equal to the work function of the metal. ... The wavelength corresponding to the threshold frequency is known as threshold wavelength.
Does work function of metal depend on frequency?
Depends upon the frequency of incident light .
How do you find the threshold frequency of a 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 .
What is the work function of the metal whose threshold frequency is?
Explanation: What is the work function (wo) of the metal whose threshold frequency (v) is 5.2 x 1014 5-1? solution : Work function of a metal is the amount of energy required to remove an electron from metal surface .
Which metal has higher threshold?
At zero stopping potential the frequency of incident radiation is more to metal A . Both the metals have the same stopping potential at different frequencies and this frequency is more than metal A. So, metal A has a higher threshold frequency. Thus, metal A has high threshold frequency.
What is a threshold frequency?
Definition of threshold frequency
: the minimum frequency of radiation that will produce a photoelectric effect .
What is the threshold frequency of zinc?
The threshold frequency of radiation for zinc is 6·50 × 1014 Hz . (a) The zinc plate is initially negatively charged. A lamp is used to shine ultraviolet radiation of frequency 6·7 × 1014 Hz onto the zinc plate.
Is frequency and threshold frequency same?
The energy of a photon is related to its’ frequency. A higher frequency means a higher energy, this relates to the E.M spectrum where Gamma radiation has a higher energy and frequency than Radio waves. ... The minimum frequency of light required to give the work function energy is called the threshold frequency.
Why different metals would have different threshold frequencies?
This is due to the work function energy of a metal depending on the position of the electron in that metal . The precise shape of the surface of a metal will determine exactly where and how electrons move in the metal. Therefore, the threshold frequency and work function can vary.
Is threshold frequency a constant?
For a given metal, there exists certain minimum frequency of the incident radiation below which no emission of photoelectrons takes place. This frequency is called threshold frequency. It is a constant quantity for a given metal surface .
What is the difference between threshold energy and threshold frequency?
Threshold energy is defined as the minimum energy required just to emit the electron from metal surface . IT is denoted by w o . Threshold frequency is defined as the minimum frequency of light which just emit electron form the metal surface if exposed to metal surface.
What is photoelectric effect define threshold frequency and work function of metal?
Threshold frequency is defined as the minimum frequency of photon required to eject an electron from the surface of metal . Also , photoelectric work function is the minimum energy required by a photon to eject an electron form the surface of metal .
What is Platinum threshold frequency?
The threshold frequency for photoelectric emission of electrons from platinum is 1.3 × 10^15 s^-1 .
What is threshold frequency H?
Planck showed that this energy difference is proportional to the frequency of occurrence ( f ) of the released quantum or the packet of energy. The proportionality constant is h with a value of h = 6. 626×10 – 34 J.s called the ” Planck’s constant.” The packet or quantum of energy is also called a “photon.”
What is the threshold wavelength of a metal?
Threshold wavelength for a metal is 5675 A .
How do you find the threshold wavelength of a metal?
To Find: Threshold wavelength of metal = λ o =? The frequency of incident light is less than the threshold frequency. No photoelectrons will be emitted from the metal surface. Ans: The threshold frequency is 1.2 x 10 15 Hz and no photoelectron will be emitted.
What is the relation between the work function and threshold wavelength of a metal?
λ=hc/W .
On what factor does work function depend on metals?
Work functions depend on the structure and chemical composition of a surface . For example, different crystallographic surfaces of the same metal or compound can have substantially different work functions. Chemical modifications of a surface can have even larger consequences.
What is the symbol of threshold frequency?
The photoelectric threshold frequency, symbolized by the Greek letter nu with subscript zero, ν 0 , 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 (ν 0 =...
What is the threshold frequency of copper?
Copper has a threshold frequency of 9×1014Hz .
Is threshold frequency same as stopping potential?
Threshold frequency is the minimum frequency of the incident light which can cause the ejection of electrons without giving them additional energy. The amount of potential that is required to stop the electron having the maximum kinetic energy from moving is known as stopping potential.
What is threshold frequency for photoelectric effect?
The threshold frequency is defined as the minimum frequency of incident radiation below which the photoelectric emission is not possible completely .
