I was watching 18.02 now and Denis Aurox, the prof. who is lecturing, mentioned that for a force to be conservative, not only was it necessary for its curl = 0 but also that F is defined and differentiable everywhere. He then went on to give the example y<i> + x<j>/x^2 + y ^2 will not be a conservative force for it is not defined at the origin.(adsbygoogle = window.adsbygoogle || []).push({});

However, I have a doubt. The first example that hit me was the Force of Gravitation. It's given by Const./ r^2 where r is the displacement between the masses. When we look at it in terms of a field, the field is not defined on the mass itself (i.e. on the point mass) and shoots to infinity as r shoots to zero. How come we define a potential in this case?

Anirudh

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# Another doubt

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