•Body response of any forces/motion that repeats itself after an interval of time.Examples.•Motion of plucked guitar string•Beating of our heart•Sleep cyclesVibration
Terms used vibratory motion(a) Time period (or) period of vibration: It is the time taken by a vibrating body to repeat the motion itself. Time period is usually expressed in seconds.(b) Cycle: It is the motion completed in one time period. (c) Periodic motion: A motion which repeats itself after equal interval of time. (d)Amplitude (X) The maximum displacement of a vibrating body from the mean position. It is usually expressed in millimeter. (e) Frequency (f) The number of cycles completed in one second is called frequency
DEGREES OF FREEDOM: The minimum number of independent coordinates required to specify the motion of a system at any instant is known as D.O.F of the system.