The minimum distance between two points having the same phase is called the wavelength of the wave, usually denoted by λ.
Sound waves are longitudinal mechanical waves that can travel through solids, liquids, or gases.
Transverse waves can propagate only in medium with shear modulus of elasticity, Longitudinal waves need bulk modulus of elasticity and are therefore, possible in all media, solids, liquids and gases.
- Mechanical waves can exist in material media and are governed by Newton’s Laws.
- Transverse waves are waves in which the particles of the medium oscillate perpendicular to the direction of wave propagation.
- Longitudinal waves are waves in which the particles of the medium oscillate along the direction of wave propagation.
- Progressive wave is a wave that moves from one point of medium to another.
speed of sound in air
(a) is independent of pressure,
(b) increases with temperature,
(c) increases with humidity.
speed is greater in solids than gas.
for echo, distance should be minimum 17m.
audible range 20-20000Hz
less than 20- infrasonic
greater than 20000- ultrasonic
