The speed of sound in air is about 331 ms⁻¹ at 0 °C and nearly 344 ms⁻¹ at 22 °C. Roughly how much extra time will the sound of thunder take to travel a distance of 1720 m, if the air temperature changes from 22°C to 0 °C? Assume that all other conditions remain unchanged.

Given that:

Distance travelled by sound = 1720 m

Speed of sound at 22 °C = 344 ms⁻¹

Speed of sound at 0 °C = 331 ms⁻¹

Time taken at 22 °C:

$$t_1 = \frac{1720}{344} = 5 \text{ s}$$

Time taken at 0 °C:

$$t_2 = \frac{1720}{331} \approx 5.2 \text{ s}$$

Extra time taken:

$$t_2 - t_1 = 5.2 - 5 = 0.2 \text{ s}$$

Hence, the sound of thunder will take approximately 0.2 s extra to travel 1720 m when the air temperature changes from 22 °C to 0 °C.