Help with physics resonance

In summary, the conversation discusses a metal cylinder with water flowing out at a rate of 10^-6 m^3/s and a tuning fork of 300 Hz placed on top of the cylinder. The question is about the water levels at which the first two resonance frequencies will be heard. It is an open-closed system and the natural frequencies are calculated using the formula f_n = \frac{nv}{4L}. The first frequency heard would be 300 Hz and one can solve for L_1 to attain 0.286m. The next frequency would be 3 times L_1. The conversation also includes a question about the beat frequency, which is always positive due to the use of absolute value in the formula f_{beat
  • #1
dekoi
There's a metal cylinder from which water is flowing out at a rate of 10^-6 m^3/s. A tuning fork of 300 Hz is placed on top of the cylinder. At what water levels will the first two resonance frequencies be heard?

It doesn't seem like a difficult problem, and it really isn't. I just can't seem to see it.

I don't think the flow rate has any signifiance in calculation; it's only useful to know that the water level is decreasing.

It's an open-closed system, so the natural frequencies are [tex]f_n = \frac{nv}{4L} [/tex] where n = 1, 3, 5, 7...

So in the first case, i think the first frequency heard would be 300 Hz. Hence, one can solve for [tex]L_1[/tex] to attain 0.286m. But how about for the next? Will it just be 3 times L_1 ? Or how do you solve for it otherwise?Thanks
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Question 2: Is it logical to ask whether the beat frequency is e.g. +4 or -4? Afterall, [tex]f_{beat} = |f_2 - f_1| [/tex] so because of the absolute value,it is always +4.
 
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  • #2
Anyone?


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  • #3


As a scientist, it is important to always question and analyze the information presented to us. In this case, it is important to clarify the context of the problem and what is being asked.

If the beat frequency is defined as the absolute value of the difference between two frequencies, then it would always be a positive value. However, if the problem is asking for the direction of the beat frequency (whether it is increasing or decreasing), then it would be logical to consider both positive and negative values.

It is also important to note that in certain situations, the beat frequency can be negative. For example, if the two frequencies are very close together and one is slightly higher than the other, the beat frequency can be negative. This is because the two waves are out of phase and their interference results in a lower amplitude.

In conclusion, it is important to clarify the context and definition of the beat frequency in order to determine whether it can be positive or negative.
 

1. What is resonance in physics?

Resonance in physics refers to the phenomenon of an object or system vibrating at its natural frequency when subjected to an external force. This results in a large amplitude of vibrations and can lead to significant effects, such as amplification or destruction of the object.

2. How does resonance occur in physics?

Resonance occurs when an external force is applied to an object or system at its natural frequency. This causes the object to vibrate with a large amplitude, as the force is continually adding energy to the system at precisely the right time to keep the vibrations going.

3. What are some real-life examples of resonance?

Some common examples of resonance in everyday life include a child swinging on a swing, a singer breaking a glass with their voice, and a tuning fork vibrating when struck. Resonance is also essential in many technological devices, such as radios and musical instruments.

4. How is resonance used in physics?

Resonance has many practical applications in physics. It is used in musical instruments to produce specific notes and in radios to tune in to specific frequencies. It is also essential in structural engineering to ensure buildings and bridges can withstand vibrations from external forces, such as wind or earthquakes.

5. What are the potential dangers of resonance?

Resonance can be dangerous if not managed properly. In structures, it can lead to increased vibrations, causing damage or even collapse. In machinery, it can cause parts to wear out quickly or malfunction. In the human body, excessive exposure to resonance frequencies can lead to health issues, such as nausea and dizziness.

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