Final answer:
The 3.0 kg ball moving at 9.0 m/s has more momentum than the 5.0 kg ball moving at 5.0 m/s.
Step-by-step explanation:
To compare the momentum of the two balls, we can use the equation:
Momentum = mass x velocity
For the first ball, with a mass of 3.0 kg and a velocity of 9.0 m/s, the momentum is:
Momentum = 3.0 kg x 9.0 m/s = 27.0 kg m/s
For the second ball, with a mass of 5.0 kg and a velocity of 5.0 m/s, the momentum is:
Momentum = 5.0 kg x 5.0 m/s = 25.0 kg m/s
Therefore, the 3.0 kg ball moving at 9.0 m/s has more momentum than the 5.0 kg ball moving at 5.0 m/s.