Αποτελέσματα Αναζήτησης
In this section, we examine some examples of damped harmonic motion and see how to modify the equations of motion to describe this more general case. A guitar string stops oscillating a few seconds after being plucked.
- 16.7: Damped Harmonic Motion
Explain critically damped system. A guitar string stops...
- 16.7: Damped Harmonic Motion
Explain critically damped system. A guitar string stops oscillating a few seconds after being plucked. To keep a child happy on a swing, you must keep pushing. Although we can often make friction and other non-conservative forces negligibly small, completely undamped motion is rare.
For example, if this system had a damping force 20 times greater, it would only move 0.0484 m toward the equilibrium position from its original 0.100-m position. This worked example illustrates how to apply problem-solving strategies to situations that integrate the different concepts you have learned.
These periodic motions of gradually decreasing amplitude are damped simple harmonic motion. An example of a damped simple harmonic motion is a simple pendulum. In the damped simple harmonic motion, the energy of the oscillator dissipates continuously.
Examples of damped harmonic oscillators include any real oscillatory system like a yo-yo, clock pendulum, or guitar string: after starting the yo-yo, clock, or guitar string vibrating, the vibration slows down and stops over time, corresponding to the decay of sound volume or amplitude in general.
Figure 1. In order to counteract dampening forces, this dad needs to keep pushing the swing. (credit: Erik A. Johnson, Flickr) A guitar string stops oscillating a few seconds after being plucked. To keep a child happy on a swing, you must keep pushing.
Give an example of a damped harmonic oscillator. (They are more common than undamped or simple harmonic oscillators.) How would a car bounce after a bump under each of these conditions? (a) overdamping; (b) underdamping; (c) critical damping. Most harmonic oscillators are damped and, if undriven, eventually come to a stop.
