Two particles of masses m and 3 m are moving toward each other along the x-axis with the same speed v. They undergo a headon elastic collision and rebound along the xaxis.

The sun’s mass is 2.0×10^ 30 kg, its radius is 7.0×10 5 km, and it has a rotational period of approximately 28 days. if the sun should collapse into a white dwarf of radius 3.5×10 3 km, what would its period be if no mass were ejected and a sphere of uniform density can model the sun both before and after?