Steady state behavior for a particle undergoing damped forced oscillations

In summary, the conversation discusses a system with a damping force undergoing forced oscillations at an angular frequency ω. The instantaneous kinetic energy and potential energy of the system are calculated using the equations K.E = 1/2 m (dx/dt)^2 and P.E = 1/2 kx^2. To find the average kinetic energy, the integral of kinetic energy over one cycle is divided by the period of oscillation. Similarly, the average potential energy is calculated by integrating the potential energy over one cycle and dividing by the period. The ratio of the average kinetic energy to the average potential energy is expressed in terms of the ratio ω/ω0. The values of ω at which the average kinetic energy and potential
  • #1
9
0

Homework Statement


consider a system with a damping force undergoing forced oscillations at an angular frequency ω
a) what is the instantaneous kinetic energy of the system?
b) what is the instantaneous potential energy of the system?
c) what is the ratio of the average kinetic energy to the average potential energy? express the answer in terms of the ratio ω/ω0
d) for what values of ω are the average kinetic energy and the average potential energy equal? what is the total energy of the system under these conditions?
e) how does the total energy of the system vary with time for an arbitrary value of ω? for what values of ω is the total energy constant in time?

Homework Equations


x = A cos(ωt-δ)
A(ω) = (F0 /mω02) [(ω0/ω)/[(ω0/ω-ω/ω0)2+(1/Q2)]1/2)]

The Attempt at a Solution


i know that K.E = 1/2 m (dx/dt)2

and P.E = 1/2 kx2

so part and b I've got .. but how do u go about calculating the Avg K.E?
 
Physics news on Phys.org
  • #2
You want to integrate the kinetic energy over one cycle:
[tex]\langle K \rangle = \frac{1}{T}\int_0^T \frac{1}{2}mv(t)^2\,dt[/tex]where T is the period of oscillation.
 
  • #3
So I would go:

ω/2∏ [itex]\int^{ω/(2∏)}_{0}[/itex] 1/2 m (dx/dt)2?

so would P.E go from 0 to A then?

Thanks a ton btw! you really helped me get started with this HW
 
  • #4
You'd still average the potential over one cycle by integrating with respect to time and dividing by the period.
 
  • #5
Thank you so very much! You are very kind! :)
 

1. What is steady state behavior?

Steady state behavior refers to the behavior of a system or object after it has been subjected to a disturbance or external force for a prolonged period of time. In the context of damped forced oscillations, it refers to the behavior of a particle after it has reached a stable equilibrium position and is oscillating at a constant amplitude and frequency.

2. How does damping affect the steady state behavior of a particle undergoing forced oscillations?

Damping refers to the dissipation of energy in a system, which can occur in various forms such as friction or air resistance. In the case of damped forced oscillations, damping reduces the amplitude of the oscillations and causes the particle to reach steady state behavior more quickly.

3. What is the role of external force in determining the steady state behavior of a particle?

The external force, also known as the driving force, is the force that is continuously applied to a particle undergoing forced oscillations. It is responsible for keeping the particle in motion and determining its amplitude and frequency of oscillation in steady state behavior.

4. Can a particle exhibit both damped and forced oscillations simultaneously?

Yes, a particle can exhibit both damped and forced oscillations simultaneously. In fact, most real-world systems experience some form of damping and are subject to external forces, resulting in damped forced oscillations.

5. How is steady state behavior affected by changes in the frequency of the external force?

The frequency of the external force plays a crucial role in determining the steady state behavior of a particle undergoing damped forced oscillations. If the frequency of the external force matches the natural frequency of the system, the amplitude of the oscillations will be maximized. If the frequency is significantly different, the amplitude will be reduced and the system may take longer to reach steady state behavior.

Suggested for: Steady state behavior for a particle undergoing damped forced oscillations

Replies
1
Views
988
Replies
6
Views
1K
Replies
2
Views
2K
Replies
1
Views
2K
Replies
1
Views
865
Replies
2
Views
770
Replies
6
Views
7K
Back
Top