College Physics

We are given thatN= 1andΔt= 0.100 s, but we must determine the change in fluxΔΦbefore we can find emf. Since the area of the loo ...

Figure 23.11(a) A motionalemf =Bℓvis induced between the rails when this rod moves to the right in the uniform magnetic field. T ...

To find the direction of the induced field, the direction of the current, and the polarity of the induced emf, we apply Lenz’s l ...

23.4 Eddy Currents and Magnetic Damping Eddy Currents and Magnetic Damping As discussed inMotional Emf, motional emf is induced ...

Figure 23.15Eddy currents induced in a slotted metal plate entering a magnetic field form small loops, and the forces on them te ...

Figure 23.17Metals can be separated from other trash by magnetic drag. Eddy currents and magnetic drag are created in the metals ...

23.5 Electric Generators Electric generatorsinduce an emf by rotating a coil in a magnetic field, as briefly discussed inInduced ...

Figure 23.21A generator with a single rectangular coil rotated at constant angular velocity in a uniform magnetic field produces ...

Figure 23.23shows a scheme by which a generator can be made to produce pulsed DC. More elaborate arrangements of multiple coils ...

Figure 23.24Steam turbine/generator. The steam produced by burning coal impacts the turbine blades, turning the shaft which is c ...

Transformers are also used at several points in the power distribution systems, such as illustrated inFigure 23.27. Power is sen ...

V (23.24) s= −Ns ΔΦ Δt , whereNsis the number of loops in the secondary coil andΔΦ/Δtis the rate of change of magnetic flux. Not ...

(23.31) Is = Ip Np Ns = (10.00 A)^50 4.17×10^4 = 12.0 mA. Discussion for (b) As expected, the current output is significantly le ...

The number of loops in the secondary is small, as expected for a step-down transformer. We also see that a small input current p ...

There arethree connections to earth or ground(hereafter referred to as “earth/ground”) shown inFigure 23.32. Recall that an eart ...

Figure 23.34Worn insulation allows the live/hot wire to come into direct contact with the metal case of this appliance. (a) The ...

Aground fault interrupter(GFI) is a safety device found in updated kitchen and bathroom wiring that works based on electromagnet ...

The basics of electrical safety presented here help prevent many electrical hazards. Electrical safety can be pursued to greater ...

Figure 23.40The heating coils of an electric clothes dryer can be counter-wound so that their magnetic fields cancel one another ...

Figure 23.42Through rapid switching of an inductor, 1.5 V batteries can be used to induce emfs of several thousand volts. This v ...