Available Answers

1. 1.

   Fill in the blanks.

   1. Light travels _____________ in a medium with greater refractive index.
   2. When a light ray passes from an optically rarer medium to an optically denser medium, it bends ___________ the normal.
   3. A ray of light coming out of a rectangular glass slab emerges ____________ to its original path.
   4. A ______________ is a circular arc of seven colours formed in the sky.
   5. A spherical mirror whose hollow surface is polished and made opaque, so that the outer surface becomes reflecting is known as __________ mirror.
   6. The distance between the ____________ and the focus is called the focal length.
   7. When the objects is at infinity. it's formed at the ____________ of the concave mirror.
   8. ___________ mirrors are used as streetlight reflectors.
2. 2.

   State weather the following statements are true ( T) or false (F). Correct the false statements.

   1. Light always travels in a straight line.
   2. As the light enters another medium , its speed changes.
   3. The refractive index of a medium is the measure of the frequency of lights in that medium with respect to the frequency of light in air.
   4. Swimming pool appears to be shallow because of dispersion.
   5. Tha radius of curvature is the radius of the sphere of which the mirror is a part.
   6. A ray passing through the focus falls normally on the reflecting surface of the mirror.
   7. A rainbow is formed when white light from the sun passes through tiny prism - like water droplets and splits into different colurs.
   8. A convex mirror always forms a magnified image behind the mirror.
3. 3.

   Show in the form of a flowchart: images formed by a concave mirror.

4. 4.

   Show in the form of a flowchart: image formed by a convex mirror.

5. 5.

   A swimming pool appears shallow than its actual depth. Give reasons.

6. 6.

   A rainbow consists of a pattern of seven colours. Give reasons.