Question

A rectangular solid made of carbon has sides of lengths 1.0 cm, 2.0 cm, and 4.0 cm, lying along the x, y, and z axes, respectively. Wires are connected to the faces and the resistance of the block is measured. The resistance will be the least when the wires are hooked up so that current flows in

Answer 1

Answer:

The correct answer is in the x-axis direction, where the distance travelled is 1.0 cm and the surface is 8 $cm^{2}$.

Explanation:

The electrical resistance is lower when the contact surface is larger and the length is shorter.

An electrical resistance is an opposition to the flow of electric current through a conductor. For a given conductor, the resistance is given by the following formula:

R = ρ * $\frac{l}{S}$

Where:

R: Electrical resistance.

ρ: Resistivity of the material.

l: Length.

S: Surface of the conductor.

Thus, the direction in which the electrical resistance is lower is when the distance is minimum and the area is greater.

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