The two ends of a rod of length $L$ and a uniform cross-sectional area $A$ are kept at two temperatures $T_1$ and $T_2 (T_1 > T_2).$ The rate of heat transfer, through the rod in a steady state is given by :
- $ \frac{ dQ}{dt}= \frac{ k(T_1 -T_2)}{LA}$
- $ \frac{ dQ}{dt}= k LA(T_1 -T_2)$
- $ \frac{ dQ}{dt}= \frac{ kA(T_1 -T_2)}{L}$
- $ \frac{ dQ}{dt}= \frac{ kL(T_1 -T_2)}{A}$
The Correct Option is C
Solution and Explanation
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Concepts Used:
Heat Transfer
What is Heat Transfer?
It is defined as the movement of heat across the border of the system due to a difference in temperature between system and its surroundings.
How is Heat Transferred?
Heat can travel from one place to another in several ways. The different modes of heat transfer include:
- Conduction - Heat flows from things with higher temp to objects with lower temp.
- Convection - Movement of liquid molecules from higher temp regions to lower temp regions.
- Radiation - Radiant heat is present in every other way in our daily lives. Thermal radiations are also known to as radiant heat. Thermal radiation is generated by the emission of electromagnetic waves.
