Posted by Jeremiah on Saturday, May 18, 2013 at 5:09pm.
The radius of planet X is 5.0 bleems. It takes 4 earth years to complete it's orbit. Another planet, Z, orbits the same sun and has an orbit with the radius of 12 bleems.
How long does it take for planet Z to complete an orbit?

Physics  bobpursley, Saturday, May 18, 2013 at 6:43pm
kepplers third law: the square of the orbital period is proportional to the cube of mean radius.
4^2/T^2=5^3/12^3
solve for period T