Typical speed of sound in air

Steps:

• Recall the standard speed of sound in dry air at 0°C is 331 m/s.
• Note that at room temperature (20°C), it increases to about 343 m/s.
• Express in scientific notation: 331 m/s ≈ 3.31 × 10² m/s; 343 m/s ≈ 3.43 × 10² m/s.
• Compare to options: only A matches this range.

Why A is correct:

• The speed of sound in air is defined by the formula v = √(γRT/M), yielding ~340 m/s under standard conditions.

Why the others are wrong:

• B (3.3 × 10³ m/s = 3300 m/s): Exceeds speeds in denser media like water (~1500 m/s).
• C (3.3 × 10⁴ m/s = 33,000 m/s): Matches approximate speed of light in vacuum, not sound.
• D (3.3 × 10⁵ m/s = 330,000 m/s): Far too high, closer to electromagnetic wave speeds in materials.

Final answer: A