Attach a long pole to the front of the car and mount a strong magnet underneath the end, so the north pole of the magnet is facing the car. Attach another strong magnet to the radiator grille of the car, with the south pole facing forward. Release the handbrake, and the magnet on the pole will pull the car forward by magnetic attraction. However, as the car moves forward, the magnet on the pole will move forward too, so the car will continue accelerating. To reverse, turn one of the magnets round so the two like poles repel.