Amoving small car has a head-on collision with a large stationary truck 7.3 times the mass of the car. which statement is true about the direction of the car after the collision if the collision is elastic?

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?