A circular wave is a wave that spreads out in all directions from a single point, like the ripples that form when a pebble is dropped into a pond. The wavefronts of a circular wave are concentric circles, and the wavelength is the distance between two adjacent wavefronts. The frequency of the wave is the number of wavefronts that pass a given point in one second.

Circular waves can be created by any object that vibrates in a circular motion, such as a tuning fork or a loudspeaker. They can also be created by the interference of two or more waves, such as the waves that form when two stones are dropped into a pond at the same time.

Circular waves have many applications, such as in sonar and radar. Sonar uses sound waves to detect objects underwater, and radar uses radio waves to detect objects in the air. Circular waves are also used in medicine, such as in ultrasound imaging and magnetic resonance imaging (MRI).