Advertisements
Advertisements
Question
What is meant by magnification? Write its expression. What is its sign for real image and virtual image?
Advertisements
Solution
Magnification produced by a spherical mirror gives how many times the image of an object is magnified with respect to the object size.
It can be defined as the ratio of the height of the image (hi) to the height of the object (ho).
Magnification = m = `"hi"/"ho"= "height of the image"/"height of the object"`
- for real image it is negative,
- for virtual image it is positive.
APPEARS IN
RELATED QUESTIONS
A student wants to project the image of a candle flame on a screen 90 cm in front of a mirror by keeping the flame at a distance of 15 cm from its pole.
(a) Suggest the type of mirror he should use.
(b) Determine the linear magnification in this case.
(c) Find the distance between the object and its image.
(d) Draw ray diagram to show the image formation in this case
Which one of these circumstances enables a concave mirror to be used as a shaving mirror?
Define linear magnification produced by a mirror.
When an object is placed 20 cm from a concave mirror, a real image magnified three times is formed. Find:
(a) the focal length of the mirror.
(b) Where must the object be placed to give a virtual images three times the height of the object?
A lens of focal length 12 cm forms an erect image three times the size of the object. The distance between the object and image is ______.
When an object is placed at a distance of 36 cm from a convex lens, an image of the same size as the object is formed. What will be the nature of image formed when the object is placed at a distance of:
20 cm from the lens?
At what distance should an object be placed from a convex lens of focal length 18 cm to obtain an image at 24 cm from it on the other side? What will be the magnification produced in this case?
Linear magnification produced by a convex lens can be ______.
If a magnification of, –1 (minus 1) is obtained by using a converging lens, then the object has to be placed:
(a) within f
(b) at 2f
(c) beyond 2f
(d) at infinity
What is the nature of the image formed by a concave mirror if the magnification produced by the mirror is +4?
