Two initially unmagnetised soft iron rods, P–Q and R–S, lie end to end. The order is magnet, P, Q, R, S. The north pole of the magnet faces P and induces magnetism in both rods. Which poles form at Q and S?
Q is south; S is north.
Q is north; S is north.
Q is north; S is south.
Q is south; S is south.