When determining the total resistance in a parallel circuit, the reciprocal of any number is that number divided by 1.

When determining the total resistance in a parallel circuit, the reciprocal of any number is that number divided by 1.

• A. 1
• B. 0
• C. 2
• D. The number itself

Answer: (A)

In a parallel circuit, the total resistance is found using reciprocals. Specifically, 1 divided by the total resistance equals the sum of the reciprocals of each individual resistance: 1/R_total = 1/R1 + 1/R2 + … This reflects why adding more parallel paths lowers the overall resistance. The reciprocal of a number means 1 divided by that number. The statement given says the reciprocal is the number divided by 1, which would equal the original number, not the reciprocal. That only happens if the number is 1; in general, the reciprocal is 1/x, not x/1. So for parallel resistances, you don’t take the resistance itself; you take its reciprocal. Then you sum those reciprocals and take the reciprocal of that sum to get R_total. For example, two resistors of 2 ohms and 3 ohms in parallel give 1/R_total = 1/2 + 1/3 = 5/6, so R_total = 6/5 = 1.2 ohms.

In a parallel circuit, the total resistance is found using reciprocals. Specifically, 1 divided by the total resistance equals the sum of the reciprocals of each individual resistance: 1/R_total = 1/R1 + 1/R2 + … This reflects why adding more parallel paths lowers the overall resistance.

The reciprocal of a number means 1 divided by that number. The statement given says the reciprocal is the number divided by 1, which would equal the original number, not the reciprocal. That only happens if the number is 1; in general, the reciprocal is 1/x, not x/1.

So for parallel resistances, you don’t take the resistance itself; you take its reciprocal. Then you sum those reciprocals and take the reciprocal of that sum to get R_total. For example, two resistors of 2 ohms and 3 ohms in parallel give 1/R_total = 1/2 + 1/3 = 5/6, so R_total = 6/5 = 1.2 ohms.