Rate of energy flow in conduction (14-23)

Question 1 of 4

Question

Cross-sectional area and length of the material through which the heat flows

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Question

Rate of heat transfer $H$ in conduction = quantity of heat $Q$ that flows divided by the time $\Delta{t}$ it takes to flow

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Review

Figure 14-20 shows an idealized situation in which conduction takes place. The cylinder of length $L$ and cross-sectional area $A$ is in thermal contact at one end with a hot region at temperature $T_{\mathrm{H}}$ and in thermal contact at the other end with a cold region at temperature $T_{\mathrm{C}}$ . Experiment shows that the rate of heat transfer is proportional to the temperature difference $T_{\mathrm{H}} - T_{\mathrm{C}}$ (the greater the temperature difference, the more rapidly heat flows). The rate of heat trans- fer is also greater if the cylinder is short ( $L$ is small) and wide ( $A$ is large). We can put these observations together into a single equation: