MCQ
Photoelectric effect was discovered by:
  • A
    Hertz.
  • B
    Hallwachs.
  • C
    Lenard.
  • D
    Millikan.

Answer

  1. Hertz.

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Assertion :   An ac generator is based on the phenomenon of self-induction.

Reason     : In single coil, we consider self-induction only.

(a) If both assertion and reason are true and the reason is the correct explanation of the assertion.

(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.

(c) If assertion is true but reason is false.

(d) If assertion is false but reason is true.

If the de-Broglie wavelengths for a proton and for a α - particle are equal, then the ratio of their velocities will be

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(b) 24.6 V

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