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CALC A 1.50-m cylinder of radius 1.10 cm is made of a complicated mixture of materials. Its resistivity depends on the distance x from the left end and obeys the formula ρ(x) = a + bx2, where a and b are constants. At the left end, the resistivity is 2.25 × 10−8 Ω · m, while at the right end it is 8.50 × I0−8 Ω · m. (a) What is the resistance of this rod? (b) What is the electric field at its midpoint if it carries a 1.75-A current? (c) If we cut the rod into two 75.0-cm halves, what is the resistance of each half?
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