Advertisements
Advertisements
Question
A lens forms an upright and diminished image of an object, irrespective of its position. What kind of lens is this? Draw an outline ray diagram to show the formation of the image. State the position and one more characteristic of the image.
Advertisements
Solution
A concave (or diverging) lens forms an upright and diminished image of an object irrespective of its position.

The outline ray diagram showing the formation of the image is given in figure. For the object AB, the image is A’B’.
The image is formed between optical centre O and focus F, in front of the lens.
The image is virtual.
RELATED QUESTIONS
A doctor has prescribed a corrective lens of power +1.5 D. Find the focal length of the lens. Is the prescribed lens diverging or converging?
Which one of the following materials cannot be used to make a lens?
The power of a lens is + 0.2 D. Calculate its focal length.
What is the unit of power of a lens? Define the unit of power of a lens.
Define the term focal length of a lens.
State the condition for the following a ray passes undeviated through the lens .
Consider the situation described in the previous problem. Where should a point source be placed on the principal axis so that the two images form at the same place?
The following diagram shows the object O and the image I formed by a lens. Copy the diagram and on it mark the positions of the lens LL’ and focus (F). Name the lens.

If focal length of a convex lens is 20 cm at what is the power of the lens?
A point object is placed at O in front of a glass sphere as shown in figure.

Show the formation of the image by the sphere.
