Ultrasonic sound – It is also called as ultrasound and is sound with frequencies larger than 20 kilohertz. The frequency of ultrasound is roughly double the limit of human being hearings in healthy individuals. Ultrasonic devices run with frequencies between 29 kHz and up to several gigahertz. Ultrasonic devices are used in detecting objects and…

Electromagnetic Waves – These are formed when an electric field comes in contact with a magnetic field. The electric field and magnetic field of an electromagnetic wave are perpendiculars (at right angles) to each other. They are also perpendicular to the direction of the EM wave. An electromagnetic wave can pass through the air, a…