Question

The amount of heat produced in a wire depends on its materials, and :

• A. Length
• B. Thickness
• C. Length and thickness
• D. None of these

Answer 1

The correct option is C

Length and thickness

Explanation:

If current ‘I' flow through a wire of resistance 'R', then the amount of heat produced in a wire can be calculated by using the given formula.

$$\begin{gathered} \mathrm{H}={\mathrm{I}}^2\mathrm{R} \\ \mathrm{Where}, \\ \mathrm{H}=\mathrm{Heat}\mathrm{produced} \\ \mathrm{I}=\mathrm{current}\mathrm{flowing}\mathrm{through}\mathrm{wire} \\ \mathrm{R}=\mathrm{resistance}\mathrm{of}\mathrm{wire} \end{gathered}$$

The resistance of the wire(R) is directly proportional to the length of the wire (L) and inversely proportional to the crossectional area of the wire(A).

$\mathrm{R}\propto \frac{\mathrm{L}}{\mathrm{A}}$

Thus, $\mathrm{H}=\frac{{\mathrm{I}}^2\times \mathrm{L}}{\mathrm{A}}$

So, the amount of heat produced in a wire depends on the material, length as well as thickness of wire.

Hence, Option(C) is correct option.