Question

2. State the differences between convex and concave mirrors? (AS)
3. Distinguish between real and virtual images. (AS)
4. How do you get a virtual image using a concave mirror? (AS)
5. What do you know about the terms given below related to spheric
a) Pole
b) Centre of curvature c) Focus
d) Radius of curvature e) Focal length f) Principal axis
g) Object distance
h) Image distance
i) Magnif
6. What do you infer from the experiment which you did to measur
image distance? (AS)
I. Application of concepts
1. Find the distance of the image when an object is placed on the
concave mirror whose radius of curvatur​

Answer 1

2-Concave mirror is converging in nature that is they centralize the light rays on point.

Concave mirror converge the light from its bent in  surface.

Convex mirror is diverging n nature that is they diverge the (spread out)the light rays on one point.

3-An optical illusion of an object which cannot  be obtained on a screen and this type of image is always erect is called virtual image.

for e.g. The image formed by plane mirror .

An optical illusion of object which can be obtained on a screen. This type of image is always inverted is called real image.

for e.g. 1-Image formed by a projector.

            2-Image formed on our retina.

4-The object should be placed in front of the concave mirror between the hole and the principal focus (i.e. object distance <20cm) to obtain an erect image. This image is virtual, erect, and enlarged and is formed behind the mirror.

5- a.Pole-This mid point of curved mirror is called pole also the intersecting point of mirror and principal axis is called pole.

b. Centre of curvature-The centre of hollow spherical mirror is called centre of curvature of the spherical mirror.

c. Focus-A point on principal axis on which the light rays converge after bending from a concave mirror.

d. Radius of curvature-The radius of hollow spherical mirror is also called Radius of curvature of curved mirror.

e. Focal length-The distance between principal focus and pole is known as focal length. It s also defined as the half of radius of curvature.

f. Principal axis-The straight line passing through centre of curvature and the pole is called Principal axis.

g. Object distance -The distance of object at a measure from pole s called object distance. It s represented by "u".

h. Image distance- The distance of image make from a point of pole is known as image distance .It is represented by "v".

i. Magnification-It is the ratio of height of image to the height of object or it can also be expressed as the ratio of image distance to the object distance in negative.

Magnification = height of image/height of object.

6- We infer from this experiment that, as candle moves from focus to infinity, it size decreases. At distance=30cm from the mirror,The image so formed is of same size and same distance from the mirror.