Solution: A circular coil with 150 loops and a radius of 10 cm is initially oriented in a 0.5 mT magnetic field, with the axis of the coil and the field at a 30o angle. After some time, the coil rotates so that the field is at an angle of 40o to the plane of the coil, and the field strength drops to 0.3 mT. What is the change in magnetic flux during this time?

Problem

A circular coil with 150 loops and a radius of 10 cm is initially oriented in a 0.5 mT magnetic field, with the axis of the coil and the field at a 30o angle. After some time, the coil rotates so that the field is at an angle of 40o to the plane of the coil, and the field strength drops to 0.3 mT. What is the change in magnetic flux during this time?