When a light ray passes from air into glass, what happens to its speed? Draw a diagram to show which way the ray of light bends.

What are the important differences between looking at a photograph of your face and looking at yourself in a plane mirror?

A convex lens forms a real and inverted image of a needle at a distance of 50 cm from it. Where is the needle placed in front of the convex lens if the image is equal to the size of the object? Also, find the power of the lens.

When an object is placed at a distance of 15cm from a concave mirror, its image is formed at 10cm in front of the mirror. Calculate the focal length of the mirror.

Define and show on a diagram, the following terms relating to a concave mirror:

1. Aperture.
2. Radius of curvature.

A ray of light is incident on a convex mirror as shown. Redraw the diagram and complete the path of this ray after reflection from the mirror. Mark angle of incidence and angle of reflection on it.

The refractive indices of glass and water with respect to air are 3/2 and 4/3 respectively. If speed of light in glass is 2×108 m/s, find the speed of light in water.

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

Light travels more quickly through water than through glass:

1. Which is optically denser: Water or glass?
2. If a ray of light passes from glass into water, which way will it bend: Towards the normal or away from the normal?

How does the light have to enter the glass:

1. To produce a large amount of bending?
2. For no refraction to happen?