Thread: mechanics - polar coordinates

A particle of mass m moves under the influence of a central force which attracts a particle with force of magnitude F(r) = m/(r^5). Assuming that the particle moves on a circular orbit of radius R where R = constant, find the period of particles motion.

Any help would be lovely, thanks!

Since force is in the radial direction,we only have centripetal acceleration which would be

Originally Posted by ignite

Since force is in the radial direction,we only have centripetal acceleration which would be

thank you very much, also i have another question....I was given the differential equation (d^2u/dphi^2) + 4/9u = 0 and told to show that the particle will eventually move along the line phi = 3pi/4...any idea how to start?

Please post entire question giving details like what is u and 'phi' and initial conditions.

Originally Posted by ignite

Please post entire question giving details like what is u and 'phi' and initial conditions.

This is the one, I can do all of it aside from the last part