A progressive wave is defined as the
onward transmission of the vibratory motion of a body in an elastic medium from
one particle to the successive particle.
Characteristics of progressive wave
1. Each particle of the
medium executes vibration about its mean position. The disturbance progresses onward
from one particle to another.
2. The particles of the
medium vibrate with same amplitude about their mean positions.
Each successive particle of the medium performs a motion similar
to that of its predecessor along the propagation of the wave, but later in
4. The phase of every
particle changes from 0 to 2π.
No particle remains
permanently at rest. Twice during each
particles are momentarily at rest at extreme positions, different particles
attain the position at different time.
6. Transverse progressive
waves are characterised by crests and troughs. Longitudinal waves are
characterised by compressions and rarefactions.
7. There is a transfer of
energy across the medium in the direction of propagation of progressive wave.
8. All the particles have
the same maximum velocity when they pass through the mean position.
The displacement, velocity and acceleration of the particle
separated by mλ are the same, where m
is an integer.