Truck on the Ramp is carrying a large (500 gram) weight, yet is pulled up the incline by a smaller (200 gram) weight hanging from a string. Even though the hanging weight is smaller, it moves a lot farther in the vertical direction. It starts out higher than the truck will ever reach, and ends up on the table top. The result is that gravity provides more energy from the lowering of the red weight than is needed to pull the truck up the incline. In fact, the truck increases in speed a little as it moves up, showing that there is some energy left over.