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Jewish_Vulcan
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I finished reading my physics textbook chapters on waves and I think I understand how resonance works but I want to verify. PLEASE ;_______;
from my understanding this is how I claim resonance works, please fix any errorsSimon Bridge said:The best way to gain understanding in this is to have a go explaining it to someone else - please tell us your understanding of how resonance works, then we can figure out how best to improve your understanding.
Good explanation, thank you for helping me understand the concept of resonance better.Simon Bridge said:Close... the incomming wave is considered to be driving the system, which, in your example, is the tube.
The system prefers particular frequencies. You seem to have understood how that happens -the wave bounces back and forth variously reinforcing and cancelling, the overall effect depend on what the system is. There are lots of ways that the system ends up preferring particular frequencies. Think: pendulum.
If you imagine sending just a pulse at the tube, the pulse enters, travels the length of the tube, reflects, and comes back. When it reaches the open end again, part of the pulse reflects , repeating the cycle. Left at that, the reflected pulse gets smaller and smaller until its gone. But if you timed the next pulse so it enters the tube right when the first one was being reflected... and if you kept doing that...
As the driving frequency gets closer to a preferred frequency, the amplitude of the wave in the system gets bigger.
This phenomena is called resonance.
It happens anywhere you get an oscillator with an osscillating driving force... i.e. A mouse wants to get a heavy nut out of a deep bowl. It is not strong enough to lift it all the way, but can give it a shove so it rolls a bit up the sides. Can you see how the mouse needs to time the shoves to get the nut out?
Thank you for the helpful reply. you would get the highest amplitude when you push the swing while it is at the 0 potential energy position right?hideelo said:Imagine the simplest case of resonance (IMO), a driven pendulum. If we first consider the pendulum, it will have it's preferred frequency, or natural frequency. What does this mean? This means that left swinging, it will have a time in it's motion when it reaches it's highest point, comes to a complete stop, and starts going the other way.
Now imagine that you want to drive this pendulum, that means you (or some machine) will apply a force to the pendulum, getting it to move in the direction you want. Let's assume you will apply some varying force force with a maximum magnitude which I will denote as F. Recall, that F = ma or m*dv/dt. This means that for your alloted force, and given mass you will be allowed to change its velocity by a given amount. The time at which you apply this maximum force is crucial, If you apply your maximum force in the -x direction when it is moving in the +x direction, then part of this force, or change in velocity (or change in momentum to be more precise), must be "wasted" in slowing down the pendulum before the remainder of it will be used to actually propel it in the direction you want it to go. If however you time it so that it will use its greatest force when the pendulum has already stopped then none of this maximum force will be "wasted" in stopping the pendulum, rather it will all go towards propelling it in the direction you want it to go. This is, to me, the best example of resonance. It shows up in many other places, but I think this model of thinking of it will get you a long way.
Lmk if I wasnt clear or if you have any other questions
Jewish_Vulcan said:Thank you for the helpful reply. you would get the highest amplitude when you push the swing while it is at the 0 potential energy position right?
@Simon Bridge said that it does not matter where you push the swing as long as it is in the positive direction there will be resonance, you say that for max resonance you have to push the swing when the PE is max in the direction that it is in motion. One of you must be not completely correct but who is it? I chose my username for a few reasons, My friends used to call me spock and I like physics and star trek tos.hideelo said:No, when the potential energy is at 0 then all of it's energy is in kinetic energy which means its moving as fast as it can and you don't want to do much then. You want to wait until all of its energy is in potential so it has as little kinetic energy as it can.
Edit: been meaning to say I love your username but what kind of name is Vulcan for a nice Jewish kid? ;-)
Jewish_Vulcan said:@Simon Bridge said that it does not matter where you push the swing as long as it is in the positive direction there will be resonance, you say that for max resonance you have to push the swing when the PE is max in the direction that it is in motion. One of you must be not completely correct but who is it? I chose my username for a few reasons, My friends used to call me spock and I like physics and star trek tos.
Resonance occurs when a wave's frequency matches the natural frequency of an object, causing the object to vibrate at a higher amplitude.
The factors that affect resonance include the frequency and amplitude of the wave, the natural frequency of the object, and the damping or resistance of the object.
Resonance plays a crucial role in everyday life, from the functioning of musical instruments to the operation of electrical circuits. It is also important in fields like acoustics, optics, and engineering.
Unlike other types of wave interactions, such as interference and diffraction, resonance only occurs when the frequency of the wave matches the natural frequency of the object. It also results in a higher amplitude compared to other wave interactions.
Yes, resonance can be harmful in certain situations. For example, it can cause buildings and bridges to collapse if their natural frequencies match the frequency of an earthquake. It can also damage delicate equipment by causing excessive vibrations.