how does a white dwarf differ from a neutron star? how does each form? what keeps each from collapsing under its own weight?

Alexander calder's mobiles are an example of motion because it uses forces of wind and water.

Agymnast dismounts off the uneven bars in a tuck position with a radius of 0.3m (assume she is a solid sphere) and an angular velocity of 2rev/s. during the dismount she stretches out into the straight position, with a length of 1.5m, (assume she is a uniform rod through the center) for her landing. the gymnast has a mass of 50kg. what is her angular velocity in the straight position?

When a 5.0kg cart undergoes a 2.2m/s increase in speed, what is the impulse of the cart