The change in density/pressure of a medium from maximum value to minimum value and again to maximum value, due to the propagation of a longitudinal wave is called a complete

Options

A. oscillation
B. frequency
C. amplitude
D. none of these

Explanation

To solve the question, we need to understand the concept of longitudinal waves and how they propagate through a medium. Here’s a step-by-step breakdown:

### Step 1: Understand Longitudinal Waves
Longitudinal waves are waves in which the displacement of the medium is parallel to the direction of wave propagation. In these waves, regions of compression (where particles are close together) and rarefaction (where particles are spread apart) alternate.

**Hint:** Recall that in a longitudinal wave, the medium's particles move back and forth in the same direction as the wave travels.

### Step 2: Identify Changes in Density and Pressure
As a longitudinal wave travels through a medium, it causes changes in both density and pressure. During the compression phase, particles are pushed closer together, resulting in increased density and pressure. Conversely, during the rarefaction phase, particles are spread apart, leading to decreased density and pressure.

**Hint:** Think about how compressing a spring changes its density and pressure compared to when it is relaxed.

### Step 3: Define Complete Oscillation
A complete oscillation refers to the full cycle of movement of the particles in the medium. This includes going from maximum density (compression) to minimum density (rarefaction) and back to maximum density (compression). This cycle represents one complete wave cycle.

**Hint:** Consider how a pendulum swings back and forth; it completes one full swing in one oscillation.

### Step 4: Relate to Wavelength and Time Period
In terms of wave properties, the distance between two successive compressions (or rarefactions) is called the wavelength. The time taken for one complete oscillation (from maximum to minimum back to maximum) is known as the time period.

**Hint:** Remember that the wavelength is the spatial measure, while the time period is a temporal measure of the wave's oscillation.

### Step 5: Conclusion
Based on the understanding of longitudinal waves and the definitions of oscillation, we conclude that the change in density/pressure of a medium from maximum value to minimum value and back to maximum value is indeed called a complete oscillation.

**Final Answer:** The correct option is "complete oscillation."

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