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STD 11 - 2. structure of atom — JEE STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceJEESTD 11 - 2. structure of atom4 Marks
MCQ
Electrons are emitted with zero velocity from a metal surface when it is exposed to radiation of wavelenght $8000\,\mathop A\limits^o $. What should be the maximum velocity of emitted electron when the same metal surface is exposed to radiation of wavelength $5000\,\mathop A\limits^o $ ? $\left( {h = 6.6 \times {{10}^{ - 34}}}\ J.s \right)$
  • A
    $5.74 \times {10^6}\ ms^{-1}$
  • ✓
    $5.74 \times {10^5}\ ms^{-1}$
  • C
    $5.74 \times {10^4}\ ms^{-1}$
  • D
    $5.74 \times {10^7}\ ms^{-1}$
✓

Answer

Correct option: B.
$5.74 \times {10^5}\ ms^{-1}$
b

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