Simple Harmonic Motion
Definition
Formula's
Applications
CONTENTS
Periodic Motion
Time Period
Frequency
Displacement
Restoring Force
Periodic Motion
It Is A Motion That Is Repeated In Equal Intervals
Of Time.
Examples:
A Rocking Chair, A Bouncing
Ball, A Vibrating Tuning Fork, A
Swing In Motion, The Earth In Its
Orbit Around The Sun, And A
Water Wave.
Displacement
The displacement of a vibrating body is the distance
from its mean position. The maximum displacement is
called the amplitude
Time Period
The period of time it takes to get back to where it
started is called time period.
It is denoted by (T).
Time is inversely proportional to frequency.
The SI unit of time period is Second.
The unit of time period is denoted by ‘s’.
Time Period
Formula:
Frequency
The number of complete cycles each second is called
Frequency.
It is denoted by (f).
Frequency is inversely proportional to time.
The SI unit of frequency is Hertz.
The unit of frequency is denoted by ‘Hz’.
Frequency
Formula:
f
Restoring Force
The force that always points back to the equilibrium
position is Restoring Force.
Restoring Force
According to Hook’s Law:
The force is needed to compress or extend a spring is
directly proportional to the distance you stretch it.
Equation:
Fr=-kx
F is the force we apply.
K is the spring constant.
X is the extension of spring material.
Simple Harmonic Motion
Definition:-
A body is undergoing SHM when the acceleration on the
body is proportional to its displacement, but acts in the
opposite direction.
Explanation
Consider a mass "m" attached to the end of an elastic spring as shown in figure "a". If
we displace the mass 'm' from its mean position 'O' to point "a“.
it is displaced by '+x' to its right, there will be elastic restoring force on the mass
equal to F in the left side
According to "Hook's Law
F = kx ---- (1)
If we release mass 'm'
it moves forward to ' O'. At point ' O' it will not stop but
moves forward towards point "b" due to inertia and
covers the same displacement -x. At point 'b' once again
elastic restoring force 'F' acts upon it but now in the right
side. In this way it continues its motion
from a to b and then b to a.
According to Newton's 2nd law of motion, force 'F' produces
acceleration 'a' in the body which is given by
F = ma ---- (2)
Comparing equation (1) & (2)
ma = -kx
Here k/m is constant term, therefore ,
a = - (Constant)x
or
This relation indicates that the acceleration of body attached to the
end elastic spring is directly proportional to its displacement.
Therefore its motion is Simple Harmonic Motion.
Applications of SHM
Car Shock Absorbers
Musical Instruments
Bungee Jumping
Diving Board
The Process of Hearing
Car Shock Musical Instruments
Absorbers
Bungee Jumping The Process of Hearing
Diving Board