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sologuitar

Member

Registered: 2022-09-19

Posts: 467

Electrical Circuits Equation

An electrical circuit contains three resistors connected in parallel. If the resistance of each is R_1, R_2, and R_3 ohms, respectively, their combine resistance R is given by the formula

(1/R) = (1/R_1) + (1/R_2) + (1/R_3)

Express R as a rational expression. Evaluate R for R_1 = 5 ohms, R_2 = 4 ohms, and R_3 = 10 ohms.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,475

Re: Electrical Circuits Equation

I'll show you the two resistor version. All you need to do is extend it to three.

Bob

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Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

sologuitar

Member

Registered: 2022-09-19

Posts: 467

Re: Electrical Circuits Equation

I'll show you the two resistor version. All you need to do is extend it to three.

Bob

Perfect. All I have to do now is evaluate. Thanks again. Bob, I am still in the review section of the textbook. Questions are going to get increasingly harder as we press forward. I really wish I could post images but my android phone A21 does not allow me to do so.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,475

Re: Electrical Circuits Equation

You'll have to do the algebra for three resistors first. I leave that as an exercise.

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

sologuitar

Member

Registered: 2022-09-19

Posts: 467

Re: Electrical Circuits Equation

You'll have to do the algebra for three resistors first. I leave that as an exercise.

Bob

Copy. Will do. Thanks again for your help.