If R is the total resistance for a parallel circuit with two resistors of resistance r1 and r2, then . Find the resistance, r1, if the total resistance R is 20 ohms, and r2 is 75 ohms. Round your answer to the nearest ohm if necessary. 1/R = 1/r1+1/r2
For a parallel circuit with two resistors, the total resistance is calculated from the expression:
1/R = 1/R1 + 1/R2
We are given the total resistance, R, which is 20 ohms and R2 which is 75 ohms. We calculate R1 as follows:
1/20 = 1/R1 + 1/75
1/R1 = 11/300
R1 = 27.27 ohms
Adding and Subtracting Rational Expressions Quick Check:
1. A. (x+4)(x-3)(x+5)
2. D. w+4/w-5
3. D. b-10/b-1
4. A. -3/5
5. C. 27 ohms
Explanation: