SOLUTION: Science and medicine. The combined resitance of two resistors R and R ___________ ___________ ___________ ___________ _ 1____ 2 in a parallel ciruit is given by the form

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Question 72486: Science and medicine. The combined resitance of two resistors R and R
_________________________________________________ 1____ 2
in a parallel ciruit is given by the formula.
R = 1/(1/R ) + (1/ R )
_:T______1______2

I am having a hard time with this problem and need some help. Thanks
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
:
I think you mean the resistors in parallel formula which is:
1%2F%28%281%2FR1%29%2B%281%2FR2%29%29
:
When there are only two resistors in parallel, it can be simplified:
Put the denominator fraction over a common denominator:
1%2F%28%28R1+%2B+R2%29%2F%28R1%2AR2%29%29
:
When you divide by a fraction, you invert and multiply:
1 * %28%28R1%2AR2%29%2F%28R1%2BR2%29%29
:
Or just: %28%28R1%2AR2%29%2F%28R1%2BR2%29%29
:
The "product over sum" equation universally used for two resistors in parallel
:
For example if you had R1 = 30 ohms and R1 = 70 ohms
Rt = %28%2830%2A70%29%2F%2830%2B70%29%29
Rt = %28%282100%29%2F%28100%29%29
Rt = 21 ohms