The point-particle tag has no wiki summary.
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How fair is it to say that all chemistry arises from failures of the ideal gas law?
I was reading here about how the ideal gas law assumes point masses and non-interaction. Is it fair to say that all chemistry arises from failures of that?
Of course, such a sweeping generalization ...
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Infinite Energy of Point Charges (in the context of classical field theories)
In the context of classical physics,is there any renormalization method to avoid infinite energy of point charges?
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Point charge 4-current derivation
How do I derive that the 4-current of a point charge is
$$j^{\mu}(x)=ec\int_{-\infty}^{+\infty}\dot{z}^{\mu}(s)\delta(x-z(s))ds$$
where $\dot{z}^{\mu}(s)$ is the 4-velocity of the charge and $s$ is ...
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Point charge moving towards a conducting plane
A point charge $q$ of mass $m$ is released from rest at a distance $d$ from an infinite grounded conducting plane. Show that the charge hits the plane after an amount of time given by:
$ \Delta t= ...
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1answer
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Discrete point particles stress energy tensor
I am trying to solve an exercise in Sean Carroll's GR book "Spacetime and Geometry". Basically we need to derive the stress-energy tensor of a perfect fluid (ie $T^{\mu\nu}=(\rho +p)U^{\mu}U^{\nu} + ...
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Does the speed of sand flow in a hourglass depend on a height of a sand column above the hourglass neck?
In a hourglass, does the sand flow through the neck depend on the amount of sand in the upper glass? If we consider a sand flow analogous to fluid flow, then it should depend linearly, but in that ...
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478 views
Point particle moving on a frictionless semicircular hill
Consider an point particle moving on a frictionless semicircular hill (curve). The particle's initial kinetic energy is equal to the potential energy on the top of the hill, i.e it has the necessary ...
