Question

A burning candle whose flame is 1 cm high is placed at a certain distance in front of a convex lens. An image of candle flame of the same size is obtained on a white screen kept behind the lens, If $f$ denotes the focal length of convex lens, the candle is placed

• A. at $f$
• B. between $f$ and 2$f$
• C. at 2$f$
• D. beyond 2$f$

Answer 1

The correct option is C at 2$f$

To obtain an image of same size as object from convex lens then object must be placed at a distance 2F from the lens.

Option C is correct.