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On the back of the new bob are two holes for mounting. They are in the EXACT SAME SPOT as the old one. The clock runs considerably slower with the new one - adjustment couldn't fix it.. I put the old one back on and after minor adjustments, it's back to keeping time. The only difference between the two pendulums are the weight, and the new one is shinier. Same diameter, same thickness.
Tell you folks what. Got a mechanical clock with a pendulum? One that actually uses the pendulum, not just for looks. Don't move the pendulum but make it heavier and get back to me. In the mean time, I have no more to say on the subject.
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Another way to check the theorem would be to make a pendulum with a disk bolted on the end. Start the swing and a stopwatch at the same time and time, say, ten swings. Then bolt a second disk on at the same location. Time it again. This will tell you if added weight changes the effective length.
Mike
If you can't get one, make one.
Hawkeye, proud to be a member of MetalworkingFun Forum since Jan 2013.
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The problem with adding weight to a pendulum is how do you do it without changing its center of mass? A few thousandths shift can have a significant effect on the period over time.
Tom
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Sounds like a perfect example of “it works in practice, but not in theory...”
Mike
SB 10K (1976) Rockwell vertical mill (1967) Rockwell 17" drill press (1946) Me (1949)