Question

which object has the greatest kinetic energy?

1. A yellow car with a mass of 500 kg moving at 12 m/s
2. A red car mass of 500 kg moving at 3m/s
3. A green car with a mass of 500 kg moving at 21 m/s
4. Blue car with a mass of 500 kg moving at 300 m/s

Answer 1

(1/2) m v^2
m is the same for all choices, look for a big v

Answer 2

The object with the greatest kinetic energy is the blue car with a mass of 500 kg moving at 300 m/s.

Answer 3

You are correct. The kinetic energy is determined by the mass and velocity squared. Thus, the object with the greatest kinetic energy would be the blue car with a mass of 500 kg moving at 300 m/s.