Photoelectric Effect

IMPORTANT

Photoelectric Effect: Overview

This topic covers concepts such as Photoelectric Effect, Threshold Frequency, Threshold Wavelength, Photoelectrons, Work Function, Characteristics of Photoelectric Effect, Einstein's Equation for Explanation of Photoelectric Effect, etc.

Important Questions on Photoelectric Effect

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The energy absorbed by each molecule (A2)  of a substance is  4.4×1019J and bond energy per molecule is  4.0×1019J.  What will be the kinetic energy of the molecule per atom?

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What do you mean by the term photoelectrons?

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The photoelectric effect is the emission of _____ or other free carriers when light shines on a material.

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The kinetic energy of the photoelectrons ejected from a metal on irradiation with light of frequency 3.8×1016 Hz is K. When irradiated with light of frequency 2.4×1016 Hz, the kinetic energy of the photoelectrons becomes K2. What is the threshold frequency ν0 of the metal?

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In case of photoelectric effect, slope of V0 vs ν curve is (where V0 - stopping potential,ν= subjected frequency)

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Photoelectric effect shows:

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Select the correct statement about the photoelectric experiment from the following.

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Light of wavelength λ, shines on a metal surface with intensity X, and the metal emits Y electrons per second of average energy Z. What will happen to Y and Z if X is doubled?

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In photoelectric effect, the kinetic energy of the photoelectrons increases linearly with the frequency of incident light.

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A zinc ball of radius, R=1 cm charged to a potential -0.5 V. The ball is illuminated by a monochromatic ultraviolet (UV) light with a wavelength 290nm. The photoelectric threshold for zinc is 332nm. The potential of ball after a prolonged exposure to the UV is

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A certain metal has a work function of Φ=2eV. It is irradiated first with 1 W of 400nm light and later with 1 W of 800nm light. Among the following, the correct statement is: [Given:Planck constant h=6.626×10-34 m2kgs-1 Speed of light (c)=3×108 ms-1]

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Ultra-violet light is shone on a zinc surface and photoelectrons are emitted. The graph shows how the stopping potential Vs varies with frequency f.

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Planck's constant may be determined from the charge of an electron e multiplied by

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A light of frequency 1.6×1016 Hz when falls on a metal plate emits electrons that have double the kinetic energy compared to the kinetic energy of emitted electrons when frequency of 1.0×1016 Hz falls on the same plate. The threshold frequency v0of the metal in Hz is

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If the work function for Caesium Cs atom is 1.9 eV, find the approximate value of its threshold wavelength.

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The maximum kinetic energy of the photoelectrons is found to be 6.63 × 10-19 J when the metal is irradiated with radiation of frequency 3 × 1015 Hz. The threshold frequency of the metal is:

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With increasing biasing voltage of a photo diode, the photocurrent magnitude:

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In photoelectric effect, the kinetic energy of the photoelectrons increases linearly with the

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When the frequency of the incident radiation on a metallic plate is doubled, KE of the photolectrons will be

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Photoelectric work function of a particular metal is 1 eV . If a light having a wavelength of 500 Å falls on the metal, then find out the approximate speed of the photoelectron emitted: (h=6.626×10-34 J/s)

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The factor on which the number of photoelectrons emitted per unit time depends in the photoelectric effect is