The longitudinal wave can be observed in

Options

A. Elastic media
B. inelastic media
C. Both (1) & (2)
D. None of these

Answer

To determine where longitudinal waves can be observed, we can follow these steps:

### Step 1: Understand the nature of longitudinal waves
Longitudinal waves are characterized by the oscillation of particles in the medium parallel to the direction of wave propagation. This means that the particles move back and forth along the same line as the wave travels.

**Hint:** Remember that in longitudinal waves, the particle motion is parallel to the wave direction.

### Step 2: Identify the mechanism of propagation
Longitudinal waves propagate through a medium due to compressions and rarefactions. Compressions are regions where particles are close together, while rarefactions are regions where particles are spread apart.

**Hint:** Think about how sound waves travel through air; they create areas of high and low pressure.

### Step 3: Consider the properties of the medium
For longitudinal waves to propagate effectively, the medium must be elastic. Elasticity allows the medium to return to its original shape after being compressed or stretched. This is where Young's modulus of elasticity comes into play, as it measures the ability of a material to deform elastically.

**Hint:** Elasticity is crucial for the medium to support the oscillations of particles.

### Step 4: Conclude the type of medium suitable for longitudinal waves
Since longitudinal waves require the presence of compressions and rarefactions, which can only occur in elastic media, we conclude that longitudinal waves can be observed in elastic media.

**Hint:** Remember that not all materials can support longitudinal waves; they must be capable of elastic deformation.

### Final Answer
The longitudinal wave can be observed in elastic media.