The correct answer is (1).
When a current flows through the BC rod in a magnetic field, a force is exerted on it due to the interaction between the magnetic field and the current. This force causes the rod to experience a torque, resulting in tension in the fibres AB and DC. The direction of the force is given by the right-hand rule, and it is strongest at the ends of the rod closest to the magnetic field.
Considering the setup, tension T1 corresponds to the force at end A, which is closest to the magnetic field. Similarly, tension T3 corresponds to the force at end D, the other end closest to the magnetic field. Tension T2 corresponds to the midpoint of the rod, where the force is weaker compared to the ends.
Therefore, tension T1 (at end A) will be greater than T2 (at the midpoint) and T3 (at end D). Hence, the correct relationship is (1)
