. 2. When asteroids collided some of the broken materials fall into Earth's orbit. What do
astronomers call the debris when it orbits planet Earth? T

Inelastic is the answer your looking for.

Ke reqd to move from 0 to 50 will be proportional to 50x50 or 2500. this is equal to w.  to change vel from 50 to 150 you need energy prop to 22500 - 2500 = 20,000. this corresponds to 8w.  best answer is a) . work reqd is prop to velocity squared. 

It would stay the same