Question

the given equation $r = \frac{0.43l}{a}$ relates the resistance $r$, in ohms, of a wire to its length $l$, in meters, and its cross - sectional area $a$, in square meters. which equation correctly expresses the length, in meters, of the wire in terms of its resistance, in ohms, and its cross - sectional area, in square meters?
a. $l = \frac{r - a}{0.43}$
b. $l = \frac{r+a}{0.43}$
c. $l = \frac{0.43r}{a}$
d. $l = \frac{ar}{0.43}$

Explanation:

Step1: Isolate \(l\) in the equation \(R = \frac{0.43l}{A}\).

Multiply both sides by \(A\): \(RA=0.43l\).

Step2: Solve for \(l\).

Divide both sides by \(0.43\): \(l=\frac{RA}{0.43}\).

Answer:

C. \(l = \frac{RA}{0.43}\)