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Standard VII

Physics

Conduction

A metal rod o...

Question

A metal rod of area of cross section $A$ has length $l$ and coefficient of thermal conductivity $K$ . The thermal resistance of the rod is :

\frac{l}{K A}

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\frac{K l}{A}

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\frac{K A}{l}

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\frac{A}{K l}

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Solution

The correct option is A $\frac{l}{K A}$
$\frac{d Q}{d t} = \frac{K A}{l}$ x temperature gradient
Thermal current $= \frac{temperature gradient}{\frac{l}{K A}}$
Thermal resistance $= \frac{l}{K A}$

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A metal rod of area of cross section A has length l and coefficient of thermal conductivity K. The thermal resistance of the rod is :

The correct option is A lKAdQdt=KAl x temperature gradientThermal current =temperature gradientlKAThermal resistance =lKA

A metal rod of area of cross section $A$ has length $l$ and coefficient of thermal conductivity $K$ . The thermal resistance of the rod is :

The correct option is A $\frac{l}{K A}$
$\frac{d Q}{d t} = \frac{K A}{l}$ x temperature gradient
Thermal current $= \frac{temperature gradient}{\frac{l}{K A}}$
Thermal resistance $= \frac{l}{K A}$