if every metal has a definite work function then why don't photoelectrons eject with same kinetic energy if the incident radiation is monochromatic and has a fixed energy?
Asked by Sahib Sodhi | 25th Oct, 2014, 06:30: PM
Work function of a metal is the minimum energy required by an electron to just escape from the metal surface with zero velocity , so as to overcome the restraining force at the surface.
Every metal has a definite work function(φo) , eg: Work function of caesium is 2.14 eV, platinum is 5.65 eV etc.
When a monochromatic light having photon frequency ν is incident on a photosensitive metal surface. The energy of the photon(hν) is spent in:
1. A part of the energy of photon is used in liberating the electrons from the metal surface which is equal to the work function φo of the metal.
2. The rest of the energy is used in imparting the maximum kinetic energy Kmax to the emitted photo electron.
i.e. we can say thay Energy of incident radiation,
So the kinetic energy of the emitted photo electron depend on the work fuction of the metal from which the electrons are emitted.Work fuction is different for different metals. Hence the photoelectrons ejected will not have same kinetic energy.
Answered by Jyothi Nair | 27th Oct, 2014, 09:50: AM
- A resistance of 600 , an inductor of 0.4 H and a capacitor of 0.01 uF are connected in series to an AC source of variable frequency. Find the frequency of AC source for which current in the circuit is maximum. Also calculate the band width and quality factor for the circuit.
- numericals based on einstein photoelectric equation
- Calculate no of photons passing through a ring of unit area in unit time if light of intensity 100 wm -2 and wavelength 400nm is fallingnormally on the ring
- Can photoelectric effect be explained on the basis of wave theory of radiation?
- How does photon theory explain photoelectric effect?
- Explain intensity of radiation in terms of wave theory and photon theory
- Why does the maximum velocity photoelectron not depend upon the intensity of radiation?
- Why are alkali metals most suited for photoelectric emission?
- Why is it difficult to remove a free electron from copper than sodium? Which has higher threshold wavelength?
- Monochromatic radiation of frequency greater than threshold value is incident on a metal. Why do all the photoelectrons not come with the same kinetic energy?
Kindly Sign up for a personalised experience
- Ask Study Doubts
- Sample Papers
- Past Year Papers
- Textbook Solutions
Verify mobile number
Enter the OTP sent to your number