Consider the circuit diagram shown. You can recognize the two resistors connected in parallel.
Measurement of the resistance of a parallel circuit. (Enlarge) |
Circuit diagram of a parallel circuit. |
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With the ohmmeter you measure a total resistance of 500 Ω. The formula describing this is a bit more complicated... 1/RTotal = 1/R1 + 1/R2 You can rewrite the formula to get...
Rtotal = ( R1 × R2 ) / ( R1 + R2 ) |
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= ( 1000 Ω × 1000 Ω ) / ( 1000 Ω + 1000 Ω )
= 500 Ω
The total resistance of a parallel circuit of resistors is therefore smaller than any of the individual resistances.
The result becomes clear when you measure the currents...
