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Electron, Photon, Photoelectric Effect and X-Rays — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsElectron, Photon, Photoelectric Effect and X-Rays1 Mark
MCQ
The work function of a metallic surface is 5.01 eV. The photo-electrons are emitted when light of wavelength 2000Å falls on it. The potential difference applied to stop the fastest photo-electrons is $\left[ h =4.14 \times 10^{-15} eV sec \right]$
  • ✓
    $1.2$ volts
  • B
    $2.24$ volts
  • C
    $3.6$ volts
  • D
    $4.8$ volts
✓

Answer

Correct option: A.
$1.2$ volts
$1.2$ volts

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