Question

A sound wave is passing through an air column in the form of compression and rarefaction. In consecutive compression and refraction:
A. Density remains constant
B. Boyle’s law is obeyed
C. Bulk modulus of air oscillates
D. There is no transfer of heatśṣ

Answer 1

In this question we will know about compression and rarefaction and compression and we know that sound waves consist of alternating compression and rarefaction or regions of high pressure or regions of low pressure. Sound waves have wavelength, amplitude, frequency, time period, and velocity as attributes.

Complete answer:
Sound propagates across an elastic medium as a mechanical disturbance in the condition of equilibrium. Sound travels in the form of waves. Sound is a longitudinal wave. There is total three types of sound waves:longitudinal wave, mechanical wave and the pressure wave. They all can travel through air, water and solid.

Now let us understand what compression is:Compression is a region of high pressure that appears as a dark strip in a wave diagram during wave propagation. Or When particles of sound waves are closer to each other is known as Compression.

Now let us understand what rarefaction is:Rarefaction is the region of expansion of particles due to compression in adjoining molecules during wave propagation, appearing in the light zone in the wave diagram. Or When particles of sound waves are away from each other this phenomenon is called rarefaction.The phenomenon of compression and rarefaction is illustrated here by the image of a tong; when we strike the tong, a sound wave is produced, and compression and rarefaction occur.

When a sound wave travels through a medium, we can say that the density of the medium i.e., air changes is due to compression and rarefaction, Boyle’s law is not obeyed.The Bulk modulus of medium remains unchanged.Because air is a poor conductor of heat, there is no heat transfer from rarefaction to compression.And time of compression as well as rarefaction is too small.

Hence, the correct option is D.

Note: Waves are determined by the direction of motion of a particle with respect to direction of propagation. In diverse motions, the variables of crest, trough, compression, and rarefaction are the variables of each other. Despite the fact that propagation differs, examining them reveals that they have similar turns that are differentiated based on the motion executed.