Question

Four convex lenses A B, C and D have focal lengths of 5 cm, 5 m, 50 cm and 15 cm respectively.Which one would you choose as a magnifying glass?

• A. A
• B. B
• C. C
• D. D

Answer 1

The correct option is A A

Answer is A.
When the object is located at a location in front of the focal point, the image will always be located somewhere on the same side of the lens as the object. Regardless of exactly where in front of F the object is located, the image will always be located on the object's side of the lens and somewhere further from the lens. The image is located behind the object.
Therefore, a converging lens produced a virtual image when the object is placed in front of the focal point. For such a position, the image is magnified and upright, thus allowing for easier viewing. Hence, the focal length of the lens should be as small as possible.
Hence, the lens A with a focal length of 5 cm will be chosen as a magnifying glass.