Which of the following represents the parallel resistance equation?

The parallel resistance equation is given by the formula 1/Rt = 1/R1 + 1/R2 for two resistors. This approach is based on the principle that in a parallel circuit, the voltage across each resistor is the same, while the total current is the sum of the currents through each individual resistor.

When resistors are connected in parallel, they provide multiple paths for the electric current. The combined effect of these pathways results in a total resistance (Rt) that is less than the resistance of the smallest individual resistor. The reciprocal of the total resistance is the sum of the reciprocals of the individual resistances. This relationship is crucial in circuit analysis because it allows for the calculation of total resistance when multiple components are connected in parallel.

The other equations provided—notably the formula for series resistors, which states that the total resistance in series is simply the sum of the individual resistances—do not apply to parallel configurations and therefore do not represent the correct relationship for calculating parallel resistance.