The differences between light and sound are as follows:
- Light can be considered to be made of waves as well as particles. Sound is only a wave. It does not show particle nature.
- Light waves are electromagnetic waves while sound waves are mechanical waves.
- Light waves are transverse while sound waves are longitudinal.
- Light waves can travel in vacuum. Sound waves require a material medium to travel, and hence, cannot travel in vacuum.
- The speed of light in a medium is constant. The velocity of sound waves can change.
- In sound waves, the particles of the medium actually oscillate. In a light wave, the electric and magnetic vectors oscillate.
- Light waves can be polarized, but sound waves cannot.
- Light waves travel much faster than sound waves. The speed of light is a physical constant. Its value is exactly 299,792,458 metres per second in vacuuum. The speed of sound is 343 metres per second in dry air at 20°C.
- And finally, a simple one - you can see light while you can hear sound.