In part (a), the flux through the rectangular loop increases as it moves into the magnetic field, and in part (b), the flux through the rotating coil varies with the angle θ θ.

The orientation of a loop with respect to a magnetic field can be changed by rotating the loop. To rotate the loop one usually mounts the loop on a structure with a handle that can rotate the loop about an axis perpendicular to the direction of the magnetic field and to the area vector of the loop as shown in the figure.

Power source produces alternating current (ac) in loop. Current exerts torque on loop. Torque initiates and maintains rotation. Rotating loop induces back emf (counteracting source emf). o the plane. A slide wire of mass m is given an initial velocityv o the right. There is no friction between t 0 nd the loop. The resistance R of the loop

The magnetic field can change magnitude or direction, as we saw in Example 23.1.1. The loop can change size or orientation relative to the magnetic field. In this section, we examine the latter case, sometimes called “motional emf”, as the induced voltage is the result of motion from the loop in which the voltage is induced.

The AC generator consists of a loop of wire rotated by some external means in a magnetic field. Use the active figure to adjust the speed of rotation and observe the effect on the emf generated.

When B-dot-A changes, what “f” causes the EMF? “A” or “dot” changes (moving or rotating loops) f = v x B = familiar magnetic force

2014年11月6日 · Consider the loop in the figure below. What is the maximum induced emf in each of the following cases if A = 600 cm2, ω = 31.0 rad/s, and B = 0.490 T? Rotating about x,y,z? This should be relatively easy since the B is constant but I can't seem to figure it out. Now then, do I take the time derivative again and set it equal to zero to find max/min?

Electric generators induce an emf by rotating a coil in a magnetic field, as briefly discussed in Motional Emf. We now explore generators in more detail. Consider the following example. The generator coil shown in Figure 13.27 is rotated through one-fourth of a revolution (from θ = 0 ° to θ = 90 °) in 15.0 ms.

When a motor is operating, two sources of emf are present: (1) the applied emf V that provides current to drive the motor, and (2) the emf induced by the generator-like action of the rotating coil.

2017年10月15日 · You will agree that an emf will be generated across the ends of a rotating rod. But just for the sake of completeness, the electrons in the rod are being forced to move along with the rod.