A car is traveling at 15 m/s
1) How fast would the car need to go to double its kinetic energy?
Kinetic Energy(KE) = 1/2 m V2
The first part (1/2 m) doesn’t change, you need a new value for V such that
V(new)2 = 2 x V(old)2
V(new) = (2 x 152) 1/2
V(new) = 4501/2
which is approx. = 21.21 meters per second.
2) By what factor does the car’s kinetic energy increase if its speed is doubled to 30 m/s?
When the velocity is doubled, the kinetic energy is four times because in the way we compute kinetic energy is by taking the square of the velocity. 2v2 = 4v2