Question

On a day when the temperature of the air is 20 C a factory siren indicating the end of a shift has a frequency of 80 Hz. What is the speed of sound on this day?

Answer 1

The speed of sound in air on a day when the temperature of the air is 20 °C is approximately 343 m/s

Step-by-step explanation:

Speed of sound in air is given as

`v_(air) = 331(m)/(s) \sqrt{(T_(K ))/(273 \ K) }= 331(m)/(s) \sqrt{1+(T_(^(\circ)C ))/(273^(\circ)C) }`

Therefore, where the temperature is given as

T = 20 °C we have

T = 293.15 K

Therefore, the speed of sound in air at 20 °C given as

`v_(air) = 331(m)/(s) \sqrt{(293 )/(273) } =331(m)/(s) \sqrt{1+(20_(^(\circ)C ))/(273^(\circ)C) } = 342.998 \ m/s`

The speed of sound in air on a day when the temperature of the air is 20 °C is 342 .998 m/s ≈ 343 m/s.