Consider the circuit shown in figure. Find (a) the current in the circuit, (b) the potential drop across the 5Ω resistor, (c) the potential drop across the 10Ω resistor. (d) Answer the parts (a), (b) and (c) with reference to figure.
(a)
Concept/Formula used:
Kirchhoff’s loop rule:
The sum of potential differences around a loop is zero.
Let the current flowing through the circuit be 
.
Applying Kirchhoff’s loop rule through the whole loop abcdea,
(b)
Concept/Formula used:
Potential Difference (V) across a resistor of resistance R when current I passes through it is given by Ohm’s law:
The potential difference across R1 is:
(c)
The potential difference across R2 is:
(d)
Let us consider the second circuit.
Applying Kirchhoff’s loop rule through the whole loop abcdea,
The potential difference across R1 is:
The potential difference across R2 is:
