1What is a mechanical wave? Write with an example.
2What is an electromagnetic wave? Give any three examples.
3Write four differences between mechanical waves and electromagnetic waves.
4Why is the speed of sound different in air, water and iron? Mention the speeds as well.
5What is the electromagnetic spectrum? Write its waves in order.
6The Sun's light reaches the Earth, but why can the sound of explosions on the Sun never be heard on the Earth?
7Why are electromagnetic waves said to be transverse waves?
8Between gamma rays and radio waves, which carries more energy? Write with reason.