4 ms·
Just the length, rather. The mass has no effect on the period.
by joe5150 11y ago
Just the length, rather. The mass has no effect on the period.
- mintplant 11y agoSo how does adding a coin change the clock's speed? The extra mass can't be changing the period of its pendulum, right? This is the bit of the article I didn't understand.
- IanCal 11y agoThe "length" that's important will be the distance to the centre of mass of the pendulum. By adding weights part-way along the pendulum, you move the centre of mass just like if you'd found a good way of adjusting the length.
- richmarr 11y agoFor a frictionless pendulum in a vacuum this is certainly true. The article repeatedly says they add weights to the pendulum though, which makes me wonder whether either (a) it's some connected mechanism they add weights to, or (b) this is somewhere reality diverges from the simple model.
- deleted 11y ago[deleted]
- rtkwe 11y agohttps://youtu.be/5qEPDXDVxvw?t=169 https://youtu.be/5qEPDXDVxvw?t=169 They're added directly to the 'pendulum shelf' which looks like it's right at the top of the pendulum. That would adjust the length up (shorter) by a tiny amount by shifting the center of mass of the pendulum up. This squares with the simple model of a pendulum.
- joe5150 11y agoIt's true the weight and shape of the bob will have an effect on the air friction applied to the system, but for a pendulum of this scale, the effect of adding a coin or two will be a negligible change in drag compared to the relatively significant change in the pendulum's center of mass.
- mkj 11y agoThe coins aren't being added at the centre of mass, so it kind of is changing the length?