Question

New sign convention for convex lens are

• A. Real object distance is positive
• B. Real object distance is negative
• C. Focal length is positive
• D. Focal length is negative

Answer 1

Answer: (B), (D)

Focal length is negative

Explanation

1. According to new sign conventions, for convex lens Objects are placed behind the pole thus the distance of the real object is negative.
2. For a convex lens focal length is held in the front of the pole.
3. Thus, the focal length is positive.

Thus, the correct option is (b) & (d) . i.e. real object distance is negative and focal length is positive.