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Speed of sound calculator

The speed of sound in air at any temperature, and how far away lightning struck from the seconds before the thunder.

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Speed of sound 343.2 m/s

How it works

v ≈ 331.3 × √(1 + T ÷ 273.15) m/s

Sound in air travels faster when it’s warmer, about 0.6 m/s more per °C: 331 m/s at freezing, 343 m/s at 20 °C. Light from a lightning flash arrives almost instantly, so the delay before the thunder is the sound’s travel time. Roughly 3 seconds per kilometer, or 5 seconds per mile.

  1. 331.3 m/s × √(1 + T ÷ 273.15) 331.3 × √(1 + 20 ÷ 273.15) = 343.2 m/s

Printed from rocketcalc.io/physics/speed-of-sound