Engineering
Physics
Conduction of Heat
Question
The rate of heat flow by conduction through a slab is Pcond. If the slab thickness is doubled, its cross-sectional area is halved, and the temperature difference across it is doubled, then the rate of heat flow becomes:
Know your College Admission Chances Based on your Rank/Percentile, Category and Home State.
Get your JEE Main Personalised Report with Top Predicted Colleges in JoSA
Solution
\[ P_{cond} = k \cdot A \cdot \frac{\Delta T}{L} \] \[ P_{cond,\text{new}} = k \cdot \frac{A}{2} \cdot \frac{2\Delta T}{2L} = \frac{1}{2} \cdot k \cdot A \cdot \frac{\Delta T}{L} = \boxed{\dfrac{P_{cond}}{2}} \]