resistance

[impsick]

sorry for the stupid question but i have a feeling even after i get an explanation it will still baffle me. but at the same time might explain alot to why things are done and how like biasing and stuff to me.

ok i understand that if you take 2 resisters of the same rsistance and ruin them side by side, parallel, you get a resistance of half the one resister. example say 1.6k + 1.6k would equal 800ohm. i mean thats a given.

what gets me is sasy you take that 1.6k with a 100ohm you would get a resistance of 100ohm. why? ok yeah the electrons like the shortest fastest rout but why?

or is my meter just a piece?

 

[Conrad Hoffman]

Actually you should get about 94 ohms, the product over the sum. A good DVM will resolve way better than this, but an inexpensive or analog meter might not.

 

[impsick]

sorry that is what i get 94 ohms. what do you mean product over sum?

 

[sandyK]

Solid State > resistance

You multiply the 2 resistor values, then divide by the added values of the 2 resistors. e.g. If you parallel 1Kohm and 10Kohm,
you get 10Kohm DIVIDED by 10,000+1,000(11,000)
The result is 909 ohms
SandyK

 

[CBS240]

Also

Rt=((R1^-1+R2^-1+R3^-1...+Rn^-1)^-1)

😉

 

[impsick]

word. thanks guys. I got it now.

 

[Nordic]

Jees !!!!!!!! Easy with the hard math....

for 2 resistors

(R1 x R2) / (R1 + R2)

 

[myhrrhleine]

sorry for the stupid question but i have a feeling even after i get an explanation it will still baffle me. but at the same time might explain alot to why things are done and how like biasing and stuff to me.

ok i understand that if you take 2 resisters of the same rsistance and ruin them side by side, parallel, you get a resistance of half the one resister. example say 1.6k + 1.6k would equal 800ohm. i mean thats a given.

what gets me is sasy you take that 1.6k with a 100ohm you would get a resistance of 100ohm. why? ok yeah the electrons like the shortest fastest rout but why?

or is my meter just a piece?

Electricity does not follow the shortest path, or the path of least resistance, but rather all available paths according to their resistance.

a 1.6k resistor allows x current to flow.
Two 1.6k resistors will allow 2 times the current to flow, equol to one resistor of 1/2 the resistance or 800 ohms.

1.6k in parallel with 100 ohms would have the current of the 100 ohm plus the current of the 1.6k resistor, or about equal to one resistor of 94 ohms.

1/R + 1/R +1/R... =1/Total