Question

A p.d. of 6 V is applied to two resistors of $3\Omega$ and $6\Omega$ connected in parallel, calculate :

(a) the combined resistance
(b) the current flowing in the main circuit
(c) the current flowing in the $3\Omega$ resistor.

Answer 1

(a) the combined resistance
$\frac{1}{R}=\frac{1}{3}+\frac{1}{6}\frac{1}{R}=\frac{2+1}{6}=\frac{3}{6}\Rightarrow R=2$

(b) the current flowing in the main circuit
$I=\frac{V}{R}=\frac{6}{2}=3Ampere$

(c) the current flowing in the 3Ω resistor.
$I_3=\frac{V}{R_3}=\frac{6}{3}=2Ampere$