Advertisements
Advertisements
Question
What is meant by magnification? Write its expression. What is its sign for the (a) real (b) virtual, image?
Solution
Magnification is the ratio of the length of image to the length of the object.
m = `1/"O"`
It is also given as
m = `-"v"/"u"`
Where, u and v is the object and image distance, respectively.
Hence, we have
- For real image: u and v are negative. So, m is negative.
- For virtual image: u is negative and v is positive. So, m is positive.
APPEARS IN
RELATED QUESTIONS
Match the items given in Column I with one or more items of Column II.
| Column I | Column II | ||
| (a) | A plane mirror | (i) | Used as a magnifying glass. |
| (b) | A convex mirror | (ii) | Can form image of objects spread over a large area. |
| (c) | A convex lens | (iii) | Used by dentists to see enlarged image of teeth. |
| (d) | A concave mirror | (iv) | The image is always inverted and magnified. |
| (e) | A concave lens | (v) | The image is erect and of the same size as the object. |
| (vi) | The image is erect and smaller in size than the object. |
Which are the two convenient rays that are chosen to construct the image by a spherical mirror for a given object? Explain with the help of suitable ray diagrams.
State the two convenient rays that are chosen to construct the image by a spherical mirror for a given object? Explain your answer with the help of suitable ray diagrams.
The diagram below in Figure, shows a convex mirror. C is its centre of curvature and F is its focus. (i) Draw two rays from A and hence locate the position of image of object OA. Label the image IB. (ii) State three characteristics of the image.
Name the mirror which always produces an erect and virtual image. How is the size of image related to the size of object?
Select the correct option:
Which mirror is used in periscope?
If the focal length of a spherical mirror is 10 cm, what is the value of its radius of curvature?
In the figure shown, the image of a real object is formed at the point I. AB is the principal axis of the mirror. The mirror must be:
