Posted by Anonymous on .
A 70.0kg runner has a speed of 5.90 m/s at one instant during a longdistance event.What is the runner's kinetic energy at this instant? If he doubles his speed to reach the finish line, by what factor does his kinetic energy change?

Physics 
Henry,
1. KE=0.5mV^2=0.5 * 70 * (5.90)^2=1218J
2. 2^2 = 4 = The factor by which the KE
is incrased.