EASY
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A photocell employs photoelectric effect to convert

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Important Questions on Dual Nature of Radiation and Matter

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The photoelectric threshold for a certain metal surface is 360 . If the metal surface is irradiated by a wavelength of 1100 , the kinetic energy of the emitted photoelectrons is

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Light of frequency 1.5 times the threshold frequency is incident on a photosensitive material. What will be the photoelectric current if the frequency is halved and intensity is doubled?
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The following graph represents the variation of photo current with anode potential for a metal surface. Here I1, I2 and I3 represents intensities and γ1,γ2,γ3 represents frequency for curves 1, 2 and 3 respectively, then

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HARD
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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Which of the following does not support the wave nature of light?
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The surface of a metal is illuminated with a light of wavelength 400 nm. The kinetic energy of the ejected photoelectrons was found to be 1.68 eV. The work function of the metal is hc=1240 eV nm,
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The work function of three photosensitive materials used to build photoelectric devices are given as : Sodium (2.75 eV), copper (4.65 eV) and gold (5.1 eV). Which of the following statements is correct. (The frequency of visible light lies in the range 4×1014 Hz to 8×1014 Hz) ?

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The continuous part of X -ray spectrum is a result of the
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Einstein was awarded the Nobel Prize for his work on
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The stopping potential for electrons emitted from a photosensitive surface illuminated by light of wavelength 491 nm is 0.710 V. When the incident wavelength is changed to a new value, the stopping potential is 1.43 V. The new wavelength is :
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The anode voltage of a photocell is kept fixed. The wavelength λ of the light falling on the cathode is gradually changed. The plate current I of the photocell varies as follows :
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The stopping potential in the context of photoelectric effect depends on the following property of incident electromagnetic radiation:
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When a beam of 10.6eV photons of intensity 2.0 W m-2 falls on a metallic surface of area 1×10-4 m2, 0.53% of the incident photons eject photoelectrons. What is the number of photoelectrons emitted per second?
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The work function of copper is 4.7 eV. If ultraviolet light of wavelength 312 nm and intensity 1.0 W m-2 is directed on a copper plate, then in the detector
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The number of photoelectrons emitted per unit area and unit time is directly proportional to [given that V>Vo
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The minimum negative potential given to anode plate at which photoelectric current becomes zero is called
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Given figure shows few data points in a photo-electric effect experiment for a certain metal. The minimum energy for ejection of electrons from its surface is: (Planck's constant h=6.62×1034 J.s)

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HARD
The radiation corresponding to 3 2  transition of hydrogen atom falls on a metal surface to produce photoelectrons. These electrons are made to enter a magnetic field of 3 × 1 0 - 4 T . If the radius of the largest circular path followed by these electrons is 10.0 mm, the work function of the metal is close to :
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When a certain photosensitive surface is illuminated with a monochromatic light of frequency ν, the stopping potential of the photo current is  -V02.  When the surface is illuminated by monochromatic light of frequency ν2, the stopping potential is -V0. The threshold frequency for photoelectric emission is