Question involving beats and finding an unknown frequency.

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In summary, the conversation discusses using beat frequencies to determine the unknown frequency of a second tuning fork, with the suggestion of attaching chewing gum to one of the forks to alter its natural frequency. By observing whether the beat frequency increases or decreases, one can infer whether the unknown frequency is greater or less than the standard frequency.
  • #1
insertnamehere
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Hello.
I think I have the answer to the following question, but I'm not sure if I got the concept.
You have a standard tuning fork whose frequency is 262 Hz and a second tuning fork with an unknown frequency. When you tap both of them on the heel of one of your sneakers, you hear beats with a frequency of 4 per second. Thoughtfully chewing you gum, your gum, you wonder whether the unknown frequency is 258Hz or 266Hz. How can you decide?

Of course, the beat frequency is the absolute value of the difference between the two frequencies, but in order to decide whether the unknown would be four more or four less than the standard, I get lost here. A hint would be really appreciated. Help!
-thank you very much for your time.
 
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  • #2
HINT: Attach a small piece of your chewing gum to one of the tuning forks thereby lowering its natural frequency. Then repeat the experiment. What can you infer?
 
  • #3
So, by lowering that tuning fork's natural frequency and repeating the experiment, I will have to see which tuning fork will continue to give me the beat frequency of 4 beats/second? I'm not sure if I got the concept right...
 
  • #4
Suppose you lower the frequency of the standard (262 Hz). The beat frequency you would then hear will either be greater than 4 beats per second or less than 4 beats per second - i.e. it would either increase or decrease the frequency separation. What would you infer in either of these cases?
 
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  • #5
ok, so does that mean that it doesn't matter which frequency the unknown tuning fork was?
 
  • #6
ok, so does that mean that it doesn't matter which frequency the unknown tuning fork was?

No. It is a means by which you can determine whether the unknown frequency of the second tuning fork is greater than or less than that of the standard tuning fork.

Ask yourself:

(a) If the beat frequency increases what does that tell you about the unknown frequency?

(b) If the beat frequency decreases what does that tell you about the unknown frequency?
 

1. How do beats occur?

Beats occur when two sound waves with different frequencies interfere with each other. This results in a periodic increase and decrease in the overall amplitude of the sound.

2. How can I calculate the beat frequency?

The beat frequency can be calculated by taking the difference between the two frequencies of the interfering sound waves. For example, if one wave has a frequency of 500 Hz and the other has a frequency of 510 Hz, the beat frequency would be 10 Hz.

3. How can I use beats to find an unknown frequency?

To find an unknown frequency using beats, you can first generate a known frequency and then adjust the unknown frequency until the beats between the two frequencies disappear. This indicates that the two frequencies are the same.

4. Can beats only occur with sound waves?

No, beats can occur with any type of wave, including electromagnetic waves. However, they are most commonly associated with sound waves due to their frequency and amplitude characteristics.

5. How can I use beats to tune musical instruments?

Beats can be used to tune musical instruments by generating a known frequency and then adjusting the instrument until the beats between the known frequency and the instrument's sound disappear. This ensures that the instrument is producing the correct frequency for a particular note.

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