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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
Threshold wavelength for photoelectric effect on sodium is $5000 \mathring A.$ Its work function is
  • A
    $15\ J$
  • B
    $16 \times 10^{-14}\ J$
  • ✓
    $4 \times 10^{-19}\ J$
  • D
    $4 \times 10^{-81}\ J$
✓

Answer

Correct option: C.
$4 \times 10^{-19}\ J$
$4 \times 10^{-81}\ J$

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