PHYSICS [2 Mark Question Answer]

When a sound wave travels through a medium, a series of compressions and rarefactions is formed between the particles of the medium due to the vibration of these particles in a direction parallel to the direction in which the sound travels. This shows that sound waves are longitudinal in nature.

Loudness of a sound depends on its amplitude. Higher the amplitude, louder is the sound. As the amplitude of a wave is directly related to the energy it carries, we can say that greater is the energy carried by a wave, louder is the sound produced.

A wave in which the particles of the medium vibrate up and down, that is, perpendicular to the direction in which the wave . is moving, is called a transverse wave. On the other hand, a wave in which the particles of the medium vibrate to-and-fro in the same direction in which the wave is moving, is called ” a longitudinal wave.

When a sound wave travels through a medium, a series of compressions and rarefactions is formed between the particles of the medium due to the vibration of these particles in a direction parallel to the direction in which the sound travels. This shows that sound waves are longitudinal in nature.

When a vibrating body moves outwards, it increases pressure on the molecules of the medium surrounding it, for example, air and causes them to come close to each other. This is known as compression. When the vibrating body moves inwards, the pressure on the molecules gets reduced. So, the gaps between the molecules increase causing them to spread out. This is known as rarefaction.

The speed of sound increases as the density of the medium increases. Since the density of solids is the maximum, followed by liquids and gases, sound travels fastest through solids, little slower through liquids and slowest through gases or air. This is the reason why a person presses his ears against the railway track to find whether a train is approaching or not.