Which term describes the substance that a wave travels through, affecting how fast the wave moves?

Which term describes the substance that a wave travels through, affecting how fast the wave moves?

• A. Wave
• B. Crest
• C. Medium
• D. Frequency

Answer: (C)

The fundamental idea is that a wave’s speed is set by the material it moves through. This material is called the medium. Different media have different properties, like elasticity (stiffness) and density, that speed up or slow down how quickly disturbances propagate. For mechanical waves such as sound or water waves, a stiffer or less dense medium generally allows faster propagation, while higher density can slow it down. When a wave moves into a new medium, its frequency stays the same, but its speed and wavelength adjust to match the properties of the new medium. That’s why speeds vary between air, water, steel, or glass—the medium is what determines how fast the wave travels.

The fundamental idea is that a wave’s speed is set by the material it moves through. This material is called the medium. Different media have different properties, like elasticity (stiffness) and density, that speed up or slow down how quickly disturbances propagate. For mechanical waves such as sound or water waves, a stiffer or less dense medium generally allows faster propagation, while higher density can slow it down. When a wave moves into a new medium, its frequency stays the same, but its speed and wavelength adjust to match the properties of the new medium. That’s why speeds vary between air, water, steel, or glass—the medium is what determines how fast the wave travels.