How Does the Amplitude of a Pendulum Affect Timekeeping in Clocks?

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The discussion focuses on how the amplitude of a pendulum affects timekeeping in clocks. Lengthening the pendulum can slow down the clock, as a longer pendulum takes more time to complete its swing. It is noted that as the amplitude decreases over time, the pendulum's path shortens, which could lead to the clock running faster if it was initially calibrated for a larger amplitude. The relationship between amplitude and timekeeping is complex, as the period of the pendulum increases slightly with larger amplitudes, affecting accuracy. Participants express uncertainty about the implications of amplitude changes on clock performance and seek clarification from a professor.
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Homework Statement
You found an old pendulum clock in the attic and are estatic

a)What should you do if the clock runs too fast?
b) You notice that the amplitudes decrease over time. Does that change anything in the clock's timing?
c) Now start playing and try to halve the pendulum frequency. How do you do that exactly?
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Hello!

So we are given this very interesting physics question, that we should only discuss and not do any calculations.

So for a) I've though this if the clock is running too fast,the way to adjust this would be to lengthen the pendelum length,my logic behind this the longer the pendelum the more time it needs to actually move, thus reducing the clock time

b) Here it says "the amplitudes decrease over time", the way I interprate this that the pendelum is moving "less" meaning its path from left to right is getting shorter. Now I wouldn't say that this affects the time of the clock, and if it would I'd reckon that time would be running slower.

c) So here we need to halve the frequence, now the way I would do it is to simply increase the length of the pendulum, to be exact take 4 times the length to reduce the frequence by half.

What do you guys think to my logic? What would you do diffrently

Thank you
 
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arhzz said:
lengthen the pendelum length,my logic behind this the longer the pendelum the more time it needs to actually move, thus reducing the clock time
Yes.
arhzz said:
I wouldn't say that this affects the time of the clock, and if it would I'd reckon that time would be running slower.
As long as the amplitude is fairly small to begin with, that is correct. But it is not truly SHM; at larger amplitudes the period does change a bit. Which way, I forget.
arhzz said:
increase the length of the pendulum, to be exact take 4 times the length to reduce the frequence by half.
Yes.
 
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arhzz said:
b) Here it says "the amplitudes decrease over time", the way I interpret this that the pendelum is moving "less" meaning its path from left to right is getting shorter.
Correct
Now I wouldn't say that this affects the time of the clock,
It does. The restoring force is less than proportional to the deviation from vertical, so the period increases (slightly) with amplitude. Conversely, if its amplitude becomes smaller and it was correct before, it will be going too fast with a smaller amplitude.
and if it would I'd reckon that time would be running slower.
Time runs at its own pace, always :smile:
 
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BvU said:
Correct
It does. The restoring force is less than proportional to the deviation from vertical, so the period increases (slightly) with amplitude. Conversely, if its amplitude becomes smaller and it was correct before, it will be going too fast with a smaller amplitude.
Time runs at its own pace, always :smile:
Okay, so the smaller the amplituted the faster the clock will tick (that is what i meant by "time of clock" poor choice of words).

Thank you for your help (both of you)!
 
haruspex said:
Yes, but that might be marked as wrong.
As I posted, constant period is a good approximation as long as the initial amplitude is not too great. See https://en.m.wikipedia.org/wiki/Pendulum#Period_of_oscillation for details.
Hmm I see, that is a bit tricky, especially since no values are given. I'll check with my professor and than I'll be able to come to a final decision. Thank you for your help!
 
haruspex said:
Yes, but that might be marked as wrong.
As I posted, constant period is a good approximation as long as the initial amplitude is not too great. See https://en.m.wikipedia.org/wiki/Pendulum#Period_of_oscillation for details.
There is some ambiguity in the problem statement. If I adjust a clock so that it runs correctly at an amplitue A, then come back six months later and see that the amplitude is, e.g. 0.5 A, the clock will be going too fast.

If the amplitude decreases while I 'm watching, the clock will be worthless, since it will probably come to a halt before it's wound up again.
 
BvU said:
There is some ambiguity in the problem statement. If I adjust a clock so that it runs correctly at an amplitue A, then come back six months later and see that the amplitude is, e.g. 0.5 A, the clock will be going too fast.

If the amplitude decreases while I 'm watching, the clock will be worthless, since it will probably come to a halt before it's wound up again.
That is what my thought process is also, I think what we are susposed to take from this question is the relationship of time and amplitude. I have not heared back from my professor for confirmation.
 
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