Question

Waves will have the highest speed in _____.air at 0°Cair at 5°Cair at 20°Cair at 30°C

Answer 1

Waves will have the highest speed in air at 30°C.

Step-by-step explanation:

The speed of wave depends on the temperature. At higher temperature, the molecules starts vibrating with more velocity. As a result, the speed of the wave increases.

It also depends on the frequency and the wavelength of the wave. If either frequency or the wavelength increase, the speed of the wave will also increase.

So, at 30 °C the wave will have highest speed.

Hence, the correct option is (d).

Answer 2

The answer is air at 30oC . This is because air at 30oC has its molecules vibrate faster than at lower temperatures. Waves travel faster in molecules that are highly excited together than less excited. Sound may seem to travel further in cold air because the warm air above it refracts sound waves, at the boundary of the two air masses, back to the cold air hence its traveles greater distances.