Hello, I'm not much of a physics entrepeneur, but I was just discussing this with my friend, and hunger for a more difinitive answer came upon me: Say you design a car, and it does 0-60km/h in 2 seconds. Now say you want to redesign the car to do exactly the same results on planet Q, which has 50% the gravity of Earth. Basically, we agreed that you would need to make sure it had the same amount of traction on Q as it did on Earth, so you would need to increase the weight. So to do that you increase its mass. I then stipulated that the Q Design of the car would need a more powerful engine in order to move the more massive body of the car. My friend disagreed, he said the engine could be equal or less powerful to still get the 0-60km/h in 2 seconds. Probably an elementry question, but what are your thoughts?