Small angle approximation to the period of a pendulum:
Plot the period versus the initial angle:
Vector potential due to a circular current flow, in cylindrical coordinates:
The components of the magnetic field:
Plot the magnitude of the magnetic field:
Resistance between the origin and the point

in an infinite 3D lattice of unit resistors:
Energy for the Onsager solution of the Ising model:
Plot of the specific heat:
Find the critical temperature:
Calculate a singular value: