You can lift a 50 pound weight by applying 20 pounds of force to a certain lever. what is the ratio of force to weight for the lever

It indicates no change in temperature and the process of matter changing its state

Answer:   [a]:   "slate" .

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. 

Answervery high orbital velocities in a very compact region;