Which would require the greater change in the Earth's orbital speed (30 km/sec):

 

        a) slowing it down so that it would crash into the Sun (0 km/sec), or
        b) speeding it up so that it would escape from the Sun (42 km/sec)?

 

Which would require the greater change in energy?

 

        a) slowing it down so that it would crash into the Sun, or
        b) speeding it up so that it would escape from the Sun?