You decide to build a home-made potato gun based on the magnetic force. The design is as follows: two parallel rails, separated by a distance of 1 m, have an accelerating length of 10 m. Your load has a mass of 0.1 kg. The current running in the rails and through the load is 10 A, the magnetic field through the circuit is 0.1 T.
a) What is the required direction of the magnetic field?