Physics
posted by Mike on .
A rectangular coil of 70 turns, dimensions 0.100 m by 0.200 m and total resistance 10.0 ohms, rotates with angular speed 32.0 rad/s about the y axis in a region where a 1.00 T magnetic field is directed along the x axis. The rotation is initiated so that the plane of the coil is perpendicular to the direction of vector B at t = 0.
(a) Calculate the maximum induced emf in the coil.
_______V
(b) Calculate the maximum rate of change of magnetic flux through the coil.
_______Wb/s
(c) Calculate the induced emf at t = 0.0500 s.
_______V
(d) Calculate the torque exerted on the coil by the magnetic field at the instant when the emf is a maximum.
_______N·m

a. induced current i = emf/R
emf e = NawB coswt
= 70*0.1*0.2 * 32 *1 * cos 32
= 38 volts
b. rate of change of flux = emf = 38 volts
c. emf e= AdB/dt= 72*0.1*0.2 * 1/5
= 0.288 volts
d. torque T = NiABw coswt