The Resistance of a Wire Varies Directly as Its Length $50$

question 115

Essay

The resistance of a wire varies directly as its length and inversely as the square of its diameter. A wire $50$ m long and $0.01$ m in diameter has a resistance of $25$ $\Omega$ . Write an equation to describe its resistance, and find the resistance of a wire made of the same material that is $20$ m long and has diameter $0.02$ m.

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Definitions:

Filtration

A process by which solids are separated from liquids or gases by passing the mixture through a medium that retains the solids.

Reabsorption

The process in the kidneys where nutrients, water, and essential ions are reabsorbed into the bloodstream from filtered fluid.

Secretion

The process by which substances are produced and discharged from a cell or gland.

Urine Concentration

The process by which the kidneys regulate the electrolyte balance and water content in the body by adjusting the volume and concentration of urine.