a) It is a sort of disturbance which goes by a medium.

b) Material phase is necessary for the propagation of mechanical waves.

c) When a wave motion goes by a phase, molecules of the phase only vibrate simple harmonically about their mean point. They do remove their position and move with the disturbance.

d)There is a continuous phase difference amongst successive particles of the phase.

e)The speed of the particle in the mean while their vibration is different at unlike position.

f) The velocity of wave motion by a particular medium is fixed. It relays only on the nature of medium not on the intensity, wavelength or frequency.

g)   Energy is transmitted along with the wave motion without any net transport of the medium.