Chapter 22
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3).  a). Usr the Right Hand's Rule: B filed points down, velocity vector points
         forward --> the force on the charges (direction of charge movement)
         is directed from the passenger's side to the driver's side of the car.
         (For right hand driving cars) Thus the driver's side will
         have more positive charge.
     b). The induced EMF is 
              EMF =  v * B * L  =>
              L = EMF/v*B = 0.0024V / 25m/s*0.000048T = 2m
         The length of the car is L= 2 meters.

12). Flux through the surface is equal to the surface area A, multiplied by
     the normal component of the magnetic field.
              PHI = A * B * cos(25degrees)
     Surface area is A = pi * r^2, where pi = 3.145...
     The flux is
              PHI = pi*r^2*B*cos(25 degrees) = 3.14*(0.1m)^2*0.078T*cos25 =
                  = 2.2*10^(-3) T*m^2

30). The magnetic field induced by the current in the wire is curling around
     the wire. In the area of the circuit, it is directed into the page.
     As the current increases the flux through the circuit also
     increases. The current induced in the circuit will have a direction such 
     that the magnetic flux generated by the induced current will oppose the 
     increse of flux due to current in the wire. It means that the flux from
     the circuit has to point out of the page and the current that can generate
     the field pointing out of the page is flowing in the counterclockwise 
     direction. Thus, the direction of current through the resistor
     is counterclockwise (from the right to the left).

52). Energy stored in the inductor is (formula 22.10)
           E = L * I^2/2 = 0.085 H * (2.5 A)^2/2 = 0.26 J

60). The transformer equation (formula 22.12)
                                           
                V_1      N_1
               ------- = ----       =>  
                V_2      N_2
     
                N_2 = N_1 * V_2/V_1 = 21 * (4320 V/120 V) = 756
     The secondary coil has N_2 = 756 turns.