Subject: diameter of sphere
Name: Niall
Who are you: Student

In April 2005, scientists claimed to have captured light from an extrasolar planet orbiting a brown dwarf in the constellation Hydra some 230 light-years from Earth. The scientists believe the planet is about five times the mass of Jupiter.

Assume the planet has the same density as Jupiter. What is the diameter of the planet?

Hi Niall.

Volume (V) is mass (M) over density and the volume of a sphere varies as the cube of the diameter (D), so since the density is the same

V varies as M
D³ varies as V

So if you multiply M by something, D is multiplied by the cube root of that factor.

Hope this helps,
Stephen La Rocque.