The maximum kinetic energy of the photoelectrons depends only on
- potential
- frequency
- incident angle
- pressure
The Correct Option is B
Solution and Explanation
Top Questions on Photoelectric Effect
- Explain the following observations using Einstein’s photoelectric equation:
(a) Photoelectric emission does not occur from a surface when the frequency of the light incident on it is less than a certain minimum value.
(b) It is the frequency, and not the intensity of the incident light which affects the maximum kinetic energy of the photoelectrons.
(c) The cut-off voltage \( V_0 \) versus frequency \( \nu \) of the incident light curve is a straight line with a slope \( \frac{h}{e} \).
- CBSE CLASS XII - 2025
- Physics
- Photoelectric Effect
- What is the photoelectric effect? Which nature of light is shown by it? Threshold frequency of a metal is \(2.3 \times 10^{14}\) Hz. If the frequency of incident light is \(8.2 \times 10^{14}\) Hz, what will be the stopping potential? Calculate work function of the metal also.
- UP Board XII - 2025
- Physics
- Photoelectric Effect
- Write down Einstein's equation for the photoelectric effect.
- UP Board XII - 2025
- Physics
- Photoelectric Effect
- Which nature of light is supported by the phenomenon of photoelectric effect? Write Einstein's equation related to photoelectric emission and briefly explain the laws of photoelectric emission on its basis.
- UP Board XII - 2025
- Physics
- Photoelectric Effect
- Threshold wavelength for a metal surface is 2000 \AA. On incidence of radiation of 1000 \AA, the kinetic energy of emitted photoelectrons will be
- UP Board XII - 2025
- Physics
- Photoelectric Effect
Questions Asked in KCET exam
- A potential at a point A is 3 V and that at another point B is 5 V. What is the work done in carrying a charge of 5 mC from B to A?
- KCET - 2025
- Electric Field
A wooden block of mass M lies on a rough floor. Another wooden block of the same mass is hanging from the point O through strings as shown in the figure. To achieve equilibrium, the coefficient of static friction between the block on the floor and the floor itself is
- KCET - 2025
- Newtons Laws of Motion
- A series LCR circuit containing an AC source of 100V has an inductor and a capacitor of reactances 24\(\Omega\) and 16\(\Omega\) respectively. If a resistance of 6\(\Omega\) is connected in series, then the potential difference across the series combination of inductor and capacitor will be
- KCET - 2025
- Electromagnetic waves
- A scientist wants to produce virus-free plant in tissue culture. Which part of the plant will he use as an explant? a) mature stem b) axillary meristem c) apical meristem d) mesophyll cell Choose the correct option from the following.
- KCET - 2025
- Tissue Culture
In an experiment to determine the figure of merit of a galvanometer by half deflection method, a student constructed the following circuit. He applied a resistance of \( 520 \, \Omega \) in \( R \). When \( K_1 \) is closed and \( K_2 \) is open, the deflection observed in the galvanometer is 20 div. When \( K_1 \) is also closed and a resistance of \( 90 \, \Omega \) is removed in \( S \), the deflection becomes 13 div. The resistance of galvanometer is nearly:
- KCET - 2025
- Viscosity
Concepts Used:
Photoelectric Effect
When light shines on a metal, electrons can be ejected from the surface of the metal in a phenomenon known as the photoelectric effect. This process is also often referred to as photoemission, and the electrons that are ejected from the metal are called photoelectrons.
Photoelectric Effect Formula:
According to Einstein’s explanation of the photoelectric effect :
The energy of photon = energy needed to remove an electron + kinetic energy of the emitted electron
i.e. hν = W + E
Where,
- h is Planck’s constant.
- ν is the frequency of the incident photon.
- W is a work function.
- E is the maximum kinetic energy of ejected electrons: 1/2 mv².
Laws of Photoelectric Effect:
- The photoelectric current is in direct proportion to the intensity of light, for a light of any given frequency; (γ > γ Th).
- There exists a certain minimum (energy) frequency for a given material, called threshold frequency, below which the discharge of photoelectrons stops completely, irrespective of how high the intensity of incident light is.
- The maximum kinetic energy of the photoelectrons increases with the increase in the frequency (provided frequency γ > γ Th exceeds the threshold limit) of the incident light. The maximum kinetic energy is free from the intensity of light.
- The process of photo-emission is an instantaneous process.