Question

Why does sound travel slower at a cold temperature?

Answer 1

Sound travels slower in cold temperatures than in hot temperatures because the particles in cold air are more closely compacted together and move slower compared to the particles of hot air. Thus the sound, vibrations of particles in the atmosphere, will travel slower.

Answer 2

It is due to a refractment of light.

Sound moves faster in warmer air than colder air the way bends away from the warm air and back towards of air.