In a certain murder investigation, it was important to discover whether the victim was long-sighted or short-sighted. How could a detective decide by examining his spectacles?

What shape are your eye-lenses:

1. When you look at your hand?
2. When you look at a distant tree?

No rainbow could be observed from the surface of Moon by the astronauts. What could be the possible reason?

What is meant by the dispersion of white light? Draw a diagram to show dispersion of white light by the glass prism.

A beam of light consisting of consists of three. namely red (R), Green (G) and yellow (Y) on the prism as shown below. Complete the diagram to show refracted and emergent ray.

Ciliary muscles of human eye can contract or relax. How does it help in the normal functioning
of the eye?

A person walking in a dark corridor enters into a brightly lit room:

1. State the effect on the pupil of the eye.
2. How does this affect the amount of light entering the eye?

Water in deep sea is blue in colour. Why?

The electronic configuration of an element is 2, 8, 4. State its:

1. Group and period in the modern periodic table.
2. Name and write its one physical property.

Why does the sky appear blue on a clear day?