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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 frequency for a metal is $10^{15}\ Hz$. Light of $\lambda = 400 \mathring A$ falls on its surface. Which of the following statements is correct
  • ✓
    No photoelectric emission takes place
  • B
    Photo$-$electrons come out with zero speed
  • C
    Photo$-$electrons come out with $10^3\ m \sec$ speed
  • D
    Photo$-$electrons come out with $10^5\ m/\sec$ speed
✓

Answer

Correct option: A.
No photoelectric emission takes place
No photoelectric emission takes place

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