Which property is unique to longitudinal waves?

Which property is unique to longitudinal waves?

• A. Compression
• B. Amplitude
• C. Wavelength
• D. Frequency

Answer: (A)

Longitudinal waves move particles in the same direction as the wave travels, which creates alternating regions of higher and lower density. The high-density regions are compression, a direct result of the medium being squeezed as the wave passes. That density variation along the direction of propagation is the feature that distinguishes longitudinal waves. In transverse waves, particles move perpendicular to the direction of travel, producing crests and troughs rather than compressions, so compression isn’t a defining feature there. Other quantities like amplitude, wavelength, and frequency apply to both types—they describe how big the oscillation is, the spatial spacing of repeating features, and how often cycles occur, but they don’t identify a property unique to longitudinal waves.

Longitudinal waves move particles in the same direction as the wave travels, which creates alternating regions of higher and lower density. The high-density regions are compression, a direct result of the medium being squeezed as the wave passes. That density variation along the direction of propagation is the feature that distinguishes longitudinal waves. In transverse waves, particles move perpendicular to the direction of travel, producing crests and troughs rather than compressions, so compression isn’t a defining feature there. Other quantities like amplitude, wavelength, and frequency apply to both types—they describe how big the oscillation is, the spatial spacing of repeating features, and how often cycles occur, but they don’t identify a property unique to longitudinal waves.