Which disturbance carries energy from one place to another through a medium?

• A. Electromagnetic Waves
• B. Amplitude
• C. Hertz
• D. Mechanical Waves

Answer: (D)

A disturbance that carries energy from one place to another through a medium is a mechanical wave. In mechanical waves, the particles of the medium—like air, water, or rope—vibrate around their rest positions and transfer energy to neighboring particles, allowing the wave to travel. Think of a sound wave traveling through air: the air particles compress and rarefy, passing energy along without the air itself traveling with the wave. Water ripples and seismic waves work the same way, moving energy through the respective medium.

Electromagnetic waves, by comparison, can move through empty space without a medium, and though they carry energy, they don’t require a material medium to propagate. The other options don’t describe a disturbance that transmits energy through a medium—amplitude is a property of the wave, and hertz is a frequency unit—so the description matches mechanical waves.