A circular coil of wire is moved vertically at a constant velocity through a horizontal magnetic field. The plane of the coil is perpendicular to the magnetic field. Draw the graph that would best represent the electric current (I) induced in the coil with time (t), if it started somewhat above the magnetic field and ended equally as far below the magnetic field?
The circular coil of wire, when moved vertically at a constant velocity through a horizontal magnetic field, cuts the magnetic flux. As a consequenc, a potential difference will be induced between the ends of the coil, and a current will flow through the coil.
The magnitude of potential difference (and hence current) can be obtained from Faraday's laws of induction.
As per the orientatin of the coil with respect to the magnetic field, when the coil is moved from up to down, starting somewhat above the magnetic field and ending equally as far below the magnetic field, the rate of cutting will vary with time and so do the current through the coil. The rate of cutting is maximum when the coil is at shortest distance from the magnetic field. So, there will be a maximum in the graph, with symmetric variation on both sides (refer to the attached image).