Forced Oscillators and their equation

Storyboard

In the case of a forced oscillator an external force is applied on the oscillating mass. This can lead to the dough being slowed or accelerated.

If the force acts synchronously (at the same rate that the mass oscillates naturally) resonances arise that can increase the amplitude of the oscillation dramatically.

>Model

ID:(52, 0)



Forced oscillator

Definition

A forced oscillator can be a system in which a mass attached to a spring is immersed in a viscous fluid, and the point where the spring is attached oscillates. This effect can be achieved by fixing the point to a rotating disk:

ID:(14098, 0)



Phase shift

Image

Phase shift is a temporal displacement of an oscillation, meaning it starts either ahead of or behind its regular timing while maintaining the same shape:

ID:(14102, 0)



Forced Oscillators and their equation

Storyboard

In the case of a forced oscillator an external force is applied on the oscillating mass. This can lead to the dough being slowed or accelerated. If the force acts synchronously (at the same rate that the mass oscillates naturally) resonances arise that can increase the amplitude of the oscillation dramatically.

Variables

Symbol
Text
Variable
Value
Units
Calculate
MKS Value
MKS Units
$A$
A
Amplitude of forced oscillation
m
$F_0$
F_0
Amplitude of the forcing force
N
$omega$
omega
Angular forcing frequency
rad/s
$z$
z
Complex number describing forced oscillation
m
$b$
b
Constant of the Viscose Force
kg/s
$x$
x
Elongation of the Spring
m
$F$
F
Forcing force
N
$\omega$
omega
Frecuencia angular del resorte
rad/s
$k$
k
Hooke Constant
N/m
$m_i$
m_i
Inertial Mass
kg
$phi$
phi
Swing phase
rad
$t$
t
Time
s

Calculations


First, select the equation:   to ,  then, select the variable:   to 

Symbol
Equation
Solved
Translated

Calculations

Symbol
Equation
Solved
Translated

 Variable   Given   Calculate   Target :   Equation   To be used



Equations

To simplify the solution of the differential equation

equation=14100

we use the solution

equation=14101

and proceed to differentiate it with respect to time to obtain the velocity

$v = \displaystyle\frac{dz}{dt} = x_0 \displaystyle\frac{d}{dt}e^{i(\omega t + \phi)}=x_0 i \omega e^{i(\omega t + \phi)} = i\omega z$



and thus the second derivative, which is equal to the first derivative of velocity

$a = \displaystyle\frac{dv}{dt} = x_0 i \omega e^{i\omega t} \displaystyle\frac{d}{dt}e^{i(\omega t + \phi)} = - \omega^2 x_0 e^{i(\omega t + \phi)}= - \omega^2 z$



which, along with

equation=1242

gives the equation

equation


Examples

A forced oscillator can be a system in which a mass attached to a spring is immersed in a viscous fluid, and the point where the spring is attached oscillates. This effect can be achieved by fixing the point to a rotating disk:

image

A simple way to model the external force is to assume that it has a magnitude of $F_0$ and undergoes oscillation with an arbitrary angular frequency $\omega$.

kyon

In the case of a damped oscillator without external forcing, the equation of motion is

equation=14081

In the case of external forcing, the force we define as

equation=14099

acts additionally on the system, leading to a modified equation of motion

kyon

In the case of an undriven damped oscillator, the equation of motion is

equation=14073

and it's important to note that the angular frequency corresponds to the system's own natural frequency. In our case, the angular frequency will match that of the system driving the oscillation. Apart from that, it's possible for the oscillation to exhibit a phase difference from the driving force. Hence, a solution in the form of

kyon

can be proposed.

If we use the equation of oscillation

equation=14101

and introduce it into

equation=14100

we obtain the equation of the forced oscillator in complex space

kyon

Phase shift is a temporal displacement of an oscillation, meaning it starts either ahead of or behind its regular timing while maintaining the same shape:

image


>Model

ID:(52, 0)