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

Rajasthan BoardEnglish MediumSTD 12 SciencePhysicsElectron, Photon, Photoelectric Effect and X-Rays1 Mark
MCQ
Ultraviolet radiations of $6.2 \ eV$ falls on an aluminium surface $($work function $4.2 \ eV ).$ The kinetic energy in joules of the fastest electron emitted is approximately
  • A
    $3.2 \times 10^{-21}$
  • ✓
    $3.2 \times 10^{-19}$
  • C
    $3.2 \times 10^{-17}$
  • D
    $3.2 \times 10^{-15}$
✓

Answer

Correct option: B.
$3.2 \times 10^{-19}$
$3.2 \times 10^{-19}$

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