The focal length of a concave mirror is 30 cm. Find the position of th – McqOptions

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1.	The focal length of a concave mirror is 30 cm. Find the position of the object in front of the mirror, so that the image is three times the size of the object.
A.	20 cm (only)
B.	40 cm (only)
C.	30 cm (only)
D.	20 cm or 40 cm
Answer» E.

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