Solving geodesic equations on the surface of a sphere

Thread starter WannabeNewton
Start date Jan 11, 2011
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Geodesic Sphere Surface

Jan 11, 2011

WannabeNewton

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Homework Statement

Find the geodesics on the surface of a sphere of radius a by:
(a) writing the geodesic equations for the spherical coordinates given by:
x = rsinTcosP
y = rsinTsinP
z = rcosT

for T and P(the r - equation can be ignored as a = constant);
(b) exhibit a particular solution of these two equations; and (c) generalize (b).

Homework Equations

Geodesic equation in general form (sorry don't know how to use LaTeX)

The Attempt at a Solution

Ok so I did part (a) and ended up with the equations for T and P as follows:

d^2T / ds^2 - (sinTcosT) * (dP / ds)^2 = 0
d^2P / ds^2 - 2cotT * (dT / ds) * (dP / ds) = 0

I am terrible at solving differential equations and basically have no idea what to do from here to find a particular solution. I was hoping someone could guide me through it.

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