You may have even heard a sonic boom as it rattles the windows in your home. Read on to find the answers to these questions. Sound travels at a constant speed, regardless of the loudness or softness of a sound. Temperature, however, does affect the speed of sound. The speed increases as the temperature increases.
Air pressure has little or no effect.
If a source of sound is moving, sound waves are shortened in the direction its moving and lengthened in the opposite. A good visual example is a boat. As a boat travels faster than the waves can spread through water, the waves pile up and form a wake behind the boat. A wake is a larger single wave. It is formed out of all the little waves that would have spread out ahead of the boat but could not.