Figure a shows a rod of resistive material. The resistance per unit length of the rod increases in positive direction of the X axis. At any position along the rod, the resistance dR of a narrow- differential-section of width dx is given by dR 5.00xdx, where dR is in ohms and a in meters. Figure b shows such a narrow section. You are to slice off a length of the rod between X = O and some position = L and then connect that length to a battery with potential difference V = 5.0V (Fig. c). You want the current in the length to transfer energy to therma energy at the rate of 6.2 W. At what position x = L in meters should you cut the rod? Keep decimla points in your aanswer. = dx 1.0 -x (m)

Figure a shows a rod of resistive material. The resistance per unit length of the rod increases in positive direction of the X axis. At any position along the rod, the resistance dR of a narrow- differential-section of width dx is given by dR 5.00xdx, where dR is in ohms and a in meters. Figure b shows such a narrow section. You are to slice off a length of the rod between X = O and some position = L and then connect that length to a battery with potential difference V = 5.0V (Fig. c). You want the current in the length to transfer energy to therma energy at the rate of 6.2 W. At what position x = L in meters should you cut the rod? Keep decimla points in your aanswer. = dx 1.0 -x (m)

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter28: Current And Resistance

Section: Chapter Questions

Problem 68PQ

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