Question

Where should an object be placed in front of convex lens to get a real image of the size of the object?

• A. At the principal focus of the lens
• B. At twice the focal length
• C. At infinity
• D. Between the optical centre of the lens and its principal focus

Answer 1

The correct option is B At twice the focal length

When object is kept at twice the focal length, image is formed at twice the focal length on the opposite side. In such a scenario, magnification is -1 and hence the image size is same as object size.