As shown in the figure, a rod PQ of length 20.0 cm and mass 200 g is suspended horizontally from a fixed point O by two threads attached to its ends, each measuring 20.0 cm in length. A uniform magnetic field of strength 0.500 T is present in the region around the wire PQ , pointing out of the page. The connecting wires between PQ and the battery are slack and do not exert any force on PQ . Determine the tension in e

Step-by-step solution

When the switch S is open, no current flows through the rod PQ . Therefore, the magnetic force acting on the rod is zero. The rod is in equilibrium under the action of its weight and the tensions in the two threads. Given that the length of the rod PQ = 20.0 cm and the lengths of the threads OP = OQ = 20.0 cm , OPQ is an equilateral triangle. The angle each thread makes with the horizontal rod is 60^ . Let T be the tension in each thread. Balancing the forces in the vertical direction: 2T (60^ ) = mg Substituting m