The document discusses wave motion and simple harmonic motion (SHM), defining periodic motion as any motion that repeats itself at equal intervals. SHM is characterized by an acceleration that is directly proportional to displacement, with key examples including pendulums and vibrating masses. The document also outlines the necessary conditions for SHM, including the need for elasticity, a restoring force, and conservation of energy.

1. Topic
Wave, Motion &
Simple Harmonic Motoin
(SHM)
BY: Ammar Bin Ahsan
Lecturer in Physics

2. Periodic Motion
Any body which
repeats its motion
in equal interval of
time is called
‘periodic motion’.

3. Oscillatory or
Vibratory Motion.
If a particle is in
periodic motion
moves back and
forth along a same
path then the
motion is said to be
‘Oscillatory or
Vibratory motion’.
VIBRATING
VIBRATING

4. Simple Harmonic
Motion (SHM)
Simple harmonic
motion (SHM)is a
special type of
oscillatory motion in
whichacceleration ‘a’
of vibratingbody is
directly proportional
to displacement ‘x’
and always has
opposite direction.
a α -x
Examples:
Vibratory motion of mass attached to the
spring on horizontal surface.
Vibratory motion of mass suspended by a
spring.
A pendulum swinging with a small
amplitude.
Vibration of tuning fork.
Vibration of molecules and atoms in
matter.

5. Characteristics or Conditions of Simple Harmonic Motion:
• A harmonic oscillator should be elastic, frictionless and should
posses inertia.
• The system must be vibratory motion, whose acceleration is
not constant.
• The oscillator must be acted upon by an elastic restoring
force.
• The restoring force must obey Hooke’s law.
• The total energy of system must remain constant.