How Do You Measure Two Resistors In Parallel?
Consider, as an example of resistors in parallel, a setup with a 9-V battery powering a circuit with a single wire leading away from the negative terminal and passing through an initial resistor, R1. The wire continues on before splitting into two wires, each passing through their own individual resistor, R2 and R3. Then the two wires rejoin before connecting again to the battery, this time to its positive terminal. Suppose also that you have an ammeter for measuring the current passing through the three resistors. Call them i1, i2 and i3. Suppose, finally, that R2 and R3 are unknown quantities, which you need to determine. Measure the currents going through the three resistors with an ammeter. Suppose, for this example, that you find i1 = 1 amp, i2 = 1/3 amp and i3 = 2/3 amp. Note that i2 + i3 = i1 is required to obey Kirchhoff’s junction rule. Apply Kirchhoff’s loop rule, which says that whichever of the two circuits an electron from the battery travels to get from the negative to th
