1. Fill in the blanks:
(a) An image that cannot be obtained on a screen is called virtual image.
(b) Image formed by a concave mirror is always virtual and smaller in size.
(c) An image formed by a plane mirror is always of the same size as that of the object.
(d) An image which can be obtained on a screen is called a real image.
(e) An image formed by a concave lens cannot be obtained on a screen.
2. (a) F
3. (a) (v)
4. Characteristics of image formed by plane mirror are:
(a) Image distance is equal to object distance.
(b) Image height is equal to object height.
(c) Image is virtual and erect
5. A, H, 0, T, U, V, W, X, Y.
6. The image that cannot be formed on a screen is called virtual image. Plane mirror always form virtual image.
7. Difference between convex lens and concave lens:
(i) Thick at middle, thin at edge.
(ii) Can form real image.
(i) Thin at middle, thick at edge.
(ii) Cannot form real image.
8. Concave mirror – used by dentist to see teeth.
Convex mirror – used in vehicles as rear view mirror.
9. Concave mirror.
10. Concave lens.
11. (ii) concave mirror.
12. (iii) 6 cm.
13. (iii) 4 m/s.