Exploring the Relationship Between Amplitude and Time in a Pendulum Clock

[arhzz]

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?

Relevant Equations

None

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

 

[haruspex]

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.

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.

increase the length of the pendulum, to be exact take 4 times the length to reduce the frequence by half.

Yes.

 

[BvU]

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

 

[arhzz]

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

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]

Okay, so the smaller the amplituted the faster the clock will tick

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.

 

[arhzz]

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!

 

[BvU]

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.

 

[arhzz]

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.