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9. Ray optics abd optical instruments — Physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 SciencePhysics9. Ray optics abd optical instruments1 Mark
MCQ
Assertion : In a movie, ordinarily $24$ frames are projected per second from one end to the other of the complete film.

Reason : The image formed on retina of eye is sustained upto $1/10\,second$ after the removal of stimulus.

  • A
    If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
  • B
    If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
  • ✓
    If the Assertion is correct but Reason is incorrect.
  • D
    If both the Assertion and Reason are incorrect.
✓

Answer

Correct option: C.
If the Assertion is correct but Reason is incorrect.
c
The image formed on retina of eye is sustained upto $\frac {1}{16}^{th}$ second after removal of stimulus. So, number of frames to be projected on the screen must be at most $16$ per second.

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