Question

How do mechanical waves differ from electromagnetic waves?

Answer 1

Here are some points which show how mechanical waves differ from electromagnetic waves -

Mechanical Waves	Electromagnetic waves
1. Mechanical waves need a material medium for their propagation. These waves cannot travel through vacuum.	1. Electromagnetic waves do not need any material medium for their propagation. These waves can travel through vacuum.
2. Speed of mechanical waves are low and depends upon the source and the medium through which they travel.	2. Electromagnetic waves travel with the speed of light (3 x 108 m/ s) in vacuum. The speed of an electromagnetic wave in any material medium is less than that in vacuum.
3. Mechanical waves are due to the vibrations of the particles of the medium.	3. Electromagnetic waves are due to the oscillating electrical and magnetic fields in space.
4. Mechanical waves may be longitudinal or transverse waves.	4. Electromagnetic waves are transverse waves.
5. Examples: Sound waves, water waves, and string waves are mechanical waves.	5. Examples: Light waves, radio and TV waves, and X-rays are electromagnetic waves.