MCQ
Photo cells are used for the
- AReproduction of pictures from the cinema film
- ✓Reproduction of sound from the cinema film
- CAutomatic switching of street light
- D$(b)$ and $(c)$ both
✓
Answer
Correct option: B.
Reproduction of sound from the cinema film
b
(d) Refer to the application of photo-cell.
(d) Refer to the application of photo-cell.
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