Ball A is a 1-kg ball moving at 2 m/s. Ball B is a 2-kg ball moving at 1 m/s? What is their
relative kinetic energies, KE?
Ball B has more KE
Balls A and B have the same KE
Ball A has more KE

Ball A has more KE

Explanation:

The kinetic energy of an object is the energy possessed by the object due to its motion, and it is calculated as

where

m is the mass of the object

v is its speed

In this problem we have, for ball A:

m =1 kg

v = 2 m/s

So, the kinetic energy of ball A is

For ball B we have

m = 2 kg

v = 1 m/s

So the kinetic energy of ball B is

So, ball A has more kinetic energy than ball B.