Thread: Third law
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Brian Gaff Brian Gaff is offline
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Default Third law

So you need the sanding equivalent of freewheeling downhill.
Brian

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On Thursday, 22 August 2019 21:34:05 UTC+1, Bill Wright wrote:
How come it needs much less effort to hold an electric sander against
the work than it does to do the work manually?


Because it's easier to hold something still than to move it.

If you turned the sander off and rubbed the wood against it, the sander
wouldn't be using any energy.

It's a bit like cycling - easier than walking, but actually less efficient
in a purely energy sense because there's the additional weight of the
bicylce to move.

Owain