Advertisements
Advertisements
Question
What information we seek by the linear magnification of the image when it is positive or negative?
Advertisements
Solution
If magnification is positive, then the image will be real and inverted, and if negative then the image will be virtual and erect.
RELATED QUESTIONS
The focal length of a convex lens is 25 cm. At what distance from the optical centre of the lens an object be placed to obtain a virtual image of twice the size?
An object is placed at a distance of 20 cm in front of a concave lens of focal length 20 cm. find: the magnification of image.
The magnification by a lens is -3. Name the lens and state how are u and v related?
Will the image formed by a magnifying glass be real or virtual?
Define magnification produced by a lens. State its unit.
Name the lens for which magnification is always less than 1.
An object is placed in front of a lens between its optical centre and the focus and forms a virtual, erect, and diminished image. Draw a ray diagram to show the formation of the image with the above-stated characteristics.
An object AB is placed between 2F1 and F1 on the principal axis of a convex lens as shown in the diagram. Copy the diagram and using three rays starting from point A, obtain the image of the object formed by the lens.

(i) Draw a ray diagram to show how the lens can be used as a ‘magnifying glass’? State the nature of the lens.
(ii) In what respect does the image in (i) above different from the image formed by a concave lens?
State two uses of magnifying glass.
