JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
In parallax method for the determination of focal length of a concave mirror, the object should always be placed :
- A between the focus (F) and the centre of curvature (C) of the mirror ONLY
- B at any point beyond the focus (F) of the mirror
- C beyond the centre of the curvature (C) of the mirror ONLY
- D between the pole (P) and the focus (F) of the concave mirror ONLY
Answer & Solution
Correct Answer
(B) at any point beyond the focus (F) of the mirror
Step-by-step Solution
Detailed explanation
Image should be real. So object should be placed beyond focus.
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