An Analytical Approach to Eddy Current in Electromagnetic Damping
An analytical method of calculating eddy current in a metallic spinning gyroscope in external magnetic field is presented. With reasonable assumptions, the problem is simplified from the time-dependent one governed by Maxwell equations to the boundary value problem of Poisson equation, which yields a closed form expression of the eddy current. The rotation frequency as a function of time is calculated, compared with experiment and the relative error is found to be 8.61%.