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Temperature distribution A thin copper rod, 4 meters in length, is heated at its midpoint, and the ends are held at a constant temperature of 0°. When the temperature reaches equilibrium, the temperature profile is given by T(x) = 40x(4 − x), where 0 ≤ x ≤ 4 is the position along the rod. The heat flux at a point on the rod equals −kT′(x), where k > 0 is a constant. If the heat flux is positive at a point, heat moves in the positive x-direction at that point, and if the heat flux is negative, heat moves in the negative x-direction.
- a. With k = 1, what is the heat flux at x = 1? At x = 3?
- b. For what values of r is the heat flux negative? Positive?
- c. Explain the statement that heat flows out of the rod at its ends.
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Calculus: Early Transcendentals (3rd Edition)
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