A D-shaped frame is made out of plastic of small square cross section and tightly wrapped uniformly with N turns of wire as shown in Figure 22.114, so that the magnetic field has essentially the same...

A D-shaped frame is made out of plastic of small square cross section and tightly wrapped uniformly with N turns of wire

as shown in Figure 22.114, so that the magnetic field has essentially the same magnitude throughout the plastic. (R is much

bigger than w.)

With a current I flowing, what is the magnetic field inside the plastic? Show the direction of the magnetic field in the

plastic at several locations.