In the circuit diagram given below, three resistors $R_1,R_2$ and $R_3$ of $5 \mathrm{\Omega },10 \mathrm{\Omega }$ and $30 \mathrm{\Omega },$ respectively are connected as shown.

Calculate:

(a) current through each resistor.

(b) total current in the circuit.

(c) total resistance in the circuit.

A potential difference of $4 \mathrm{V}$ is applied to two resistors of $6 \mathrm{\Omega }$ and $2 \mathrm{\Omega }$ connected in series. Calculate:

(a) the combined resistance

(b) the current flowing

(c) the potential difference across the $6 \mathrm{\Omega }$ resistor

A potential difference of $6 \mathrm{V}$ is applied to two resistors of $3 \mathrm{\Omega }$ and $6 \mathrm{\Omega }$ connected in parallel. Calculate:

(a) the combined resistance

(b) the current flowing in the main circuit

(c) the current flowing in the $3 \mathrm{\Omega }$ resistor.