How will you distinguish between a plane mirror, a concave mirror and a convex mirror without touching them?

If two lenses (convex) are in contact with each other, what happens to the ray after refraction?

What is the magnification produced by a rear view mirror fitted in vehicles?

An object is placed at a distance of 30 cm from a concave lens of focal length 15 cm. List four characteristics (nature, position, etc.) of the image formed by the lens.

Name the type of mirrors used in the design of solar furnaces. Explain how high temperature is achieved by this device.

Explain with the help of a diagram, why a pencil partly immersed in water appears to be bent at the water surface.

Name the lens which always forms a virtual image of an object.

State the two laws of reflection of light.

A vertical ray of light strikes the horizontal surface of some water:

1. What is the angle of incidence?
2. What is the angle of refraction?

A star appears slightly higher (above) than its actual position in the sky illustrate it with the help of a labelled diagram.