Chapter 9, Problem 9STP

To determine

To choose: The correct option.

Answer to Problem 9STP

Option B and Option D

Explanation of Solution

Introduction:

When a longitudinal wave travels through any medium, it vibrates the medium particles in the direction of propagation of wave and hence contraction and rarer fraction is formed.

Electromagnetic wave propagates in medium and without medium also and this illustration does not show the movement of an electromagnetic wave.

Transverse wave oscillates medium particle perpendicular to the direction of propagation of wave. Thus, the option C is incorrect.

Sound wave is a longitudinal wave.A longitudinal wave vibrates the medium particle in the same direction in which they are travelling.Thus, at some points, the density of particles gets higher and hence contraction in medium is formed while at density of particles gets rarer and hence rarer fraction is formed.

  

Given figure represents the same condition.Therefore, it shows a longitudinal wave.

Conclusion:

Thus, the option B and option D is correct.