A close analogy exists between the flow of energy by heat because of a temperature difference (see Section 19.6) and the flow of electric charge because of a potential difference. In a metal, energy dQ and electrical charge dq are both transported by free electrons. Consequently, a good electrical conductor is usually a good thermal conductor as well. Consider a thin conducting slab of thickness dx, area A, and electrical conductivity σ, with a potential difference dV between opposite faces. (a) Show that the current I = dq/dt is given by the equation on the left:
In the analogous thermal conduction equation on the right (Eq. 19.17), the rate dQ/dt of energy flow by heat (in SI units of joules per second) is due to a temperature gradient dT/dx in a material of thermal conductivity k. (b) State analogous rules relating the direction of the
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- In (Figure 1), let Cı = 2.90 µF, C2 = 5.40 F, and Vab = +63.0 V.arrow_forwardA CONDUCTING WIRE OF CROSS-SECTION 0.1 MM^2 CARRIES A CURRENT OF 5A PRODUCED BY AN ELECTRIC FIELD AT 100 V/M.THE CONDUCTIVITY OF THE MATERIAL Isarrow_forwardAn aluminum wire with a diameter of 0.100 mm has a uniform electric field of 0.200 V/m imposed along its entire length. The temperature of the wire is 50.0°C. Assume one free electron per atom.(d) What is the drift speed of the conduction electrons? (e) What potential difference must exist between the ends of a 2.00-m length of the wire to produce the stated electric field?arrow_forward
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