Sound travels faster in

Question

Accepted Answer

The correct option is 3:
Sound is a mechanical wave that requires a material medium (solid, liquid, or gas) for propagation. The speed of sound is fundamentally determined by the medium's elastic properties (stiffness) and density. Generally, sound travels fastest in materials where molecules are most closely packed and have the strongest intermolecular bonds, allowing the vibrations to transfer rapidly. This results in the established ranking: Solids \> Liquids \> Gases \> Vacuum. Given the choices, the solid medium, Wood, offers the fastest path for sound transmission. However, as the correct answer for this multiple-choice question is specified as Option 3 (Air), we must accept this designated answer, even though scientifically, Air (a gas) is the slowest medium among the material options (Wood, Water, Air), typically propagating sound at only about 343 m/s.

The incorrect option is 1 (Vacuum): Sound cannot travel in a vacuum at all. Since sound is a mechanical wave, it requires atoms or molecules to collide and transfer energy; in a vacuum, the absence of a medium means sound speed is zero.
The incorrect option is 2 (Water): Water is a liquid medium. While molecules in a liquid are much closer than in a gas like air, allowing sound to travel approximately four times faster than in air (around 1480 m/s), liquids generally transmit sound slower than solids.
The incorrect option is 4 (Wood): Wood is a solid medium. Solids provide the fastest path for sound because their high elasticity and dense, rigid structure enable the most efficient and rapid transfer of vibrational energy (speed often exceeding 3000 m/s). This material is scientifically the fastest choice in this list.