Question

To form an enlarged image of an object in front of a convex lens, it should be placed _____.

• A. anywhere between $2$F and O
• B. behind the focal point
• C. at the center of curvature
• D. at $2$F

Answer 1

The correct option is A

anywhere between $2$F and O

An object placed between the focus and center of curvature:

1. A beam parallel to the primary axis passes through focus F following refraction. Some other beam, on the other hand, travels thru the optical center C with no divergence.
2. These two refracted light waves intersect, and the resulting picture is bigger than the object, both actual and inverted.

An object is at principal focus:

1. A ray parallels the principal axis following passing through the focus; at the same time, another beam passes thru the optical center and continues unbroken. Both refracted beams are parallel to one another and never intersect.
2. As a result, the picture will be formed at infinity. The resulting image is greatly magnified, actual, and reversed.

An object is between the principal focus and optical center of a lens:

1. After refraction, a parallel beam passes through the focus. The other beam passes through the optical center without interruption. Two refracted rays cannot collide to generate a unique picture.
2. As a result of the refracted rays being extended backward by dotted, a virtual, erect, and significantly magnified picture is created on the very same side of the lens.

A convex lens should have been placed anywhere between 2F and O to generate an enlarged picture of an item in front of it.

Therefore, option A is the correct choice.