An ohmic conductor is carrying a current. The cross-sectional area of the wire changes from one end of the wire to the other. Which of the following quantities vary along the wire?
A. The resistivity
B. The current
C. The current density
D. The electric field
1.A only
2.B only
3.C only
4.D only
5.A and B only
6.C and D only
7.A, B, C, and D
8.None of the above
6
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