Question

You are given a copper bar of dimensions 3 cm × 5 cm × 8 cm and asked to attach leads to it in order to make a resistor. If you want to achieve the smallest possible resistance, you should attach the leads to the opposite faces that measure.

A) 3 cm × 5 cm.

B) 3 cm × 8 cm.

C) 5 cm × 8 cm.

D) Any pair of faces produces the same resistance.

Answer 1

`c. 5cm * 8cm`

Step-by-step explanation:

The dimensions
`5cm* 8cm` have the highest cross-sectional area combination of
`40cm^2`.

-Resistance reduces with an increase in cross sectional area.

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`Reason-`Electrons have alarger area to flow through.