There are three essential laws governing the electrical circuit. These are Ohm’s Law, Kirchhoff’s Current Law and Kirchhoff’s Voltage Law. Basically these are utilized to solve any electrical circuit problem.

Ohm’s Law states that voltage across a resistance is current passing through it times the resistance.

Kirchhoff’s Current Law (KCL) states that at any junction, the sum of incoming currents is equal to sum of outgoing currents,

Kirchhoff’s Voltage Law (KVL) states that sum of voltage rises is equal to sum of voltage drops around a closed loop,

Solutions for electrical circuit (network) problems can be arrived at by using the following theorems / laws.

- Ohm’s Law
- Kirchhoff’s Current Law (KCL)
- Kirchhoff’s Voltage Law (KVL)
- Thevenin’s Theorem
- Norton’s Theorem
- Superposition Theorem
- Mesh Analysis
- Nodal Analysis
- Source Transformation
- Star-Delta Transformation (aka Wye-Delta)
- Tellegen’s Theorem
- Bartlett’s Bisection Theorem
- and other shortcut methods

## Multiple Choice Questions

Q01. The amount of work done in moving a unit positive charge from one point to another is, (a) Charge (b) Potential Difference (c) Resistance (d) Capacitance

Q02. The potential difference between two points is said to be ______, if 1 Joule of work is done in moving 1 Coulomb of electric charge from one point to another (a) 1 milliVolt (b) 1 megaVolt (c) 1 kiloVolt (d) 1 Volt

Q03. Charge of an electron (e) = _____ C (a) 1.6 x 10^{-11}(b) 3.2 x 10^{-19}(c) 1.9 x 10^{-16}(d) 1.6 x 10^{-19}

Q04. 1 Volt = ________ (a) 1 milliVolt (b) 1000 milliVolt (c) 0.1 kiloVolt (d) 1 microVolt

Q05. Ohm’s Law can mathematically be stated as: (Symbols have their usual meanings) (a) C = I x A (b) A = I x V (c) R = I x C (d) V = I x R

Q06. If 2 Ampere current flows through the conductor when 15 Volt potential difference is applied across it, the resistance is ____ Ohm (a) 30 (b) 5 (c) 7.5 (d) 1

Q07. Effective Resistance of resistors in Parallel is ________ of all resistors (a) Less than Maximum (b) Less than Least (c) More than Maximum (d) More than Least

Q08. The quantity of heat (H) generated in a conductor of Resistance (R), when a current (I) flows through it for the time (t), depends on (a) Current (I) (b) Resistance of conductor (R) (c) Time for which current flows (t) (d) All of the above Ans:

Q09. Resistivity of Ebonite is ______ (ohm-m) (a) 10^{-8}to 10^{-6}(b) 10^{3}to 10^{5}(c) 10^{7}to 10^{8}(d) 10^{15}to 10^{17}

Q10. Effective Resistance of resistors in Series is ________ of all resistors (a) Less than Maximum (b) Less than Minimum (c) More than Maximum (d) More than Minimum

Answers to MCQs.

Q01. (b) Potential Difference

Q02. (d) 1 Volt

Q03. (d) 1.6 x 10^{-19}

Q04. (b) 1000 milliVolt

Q05. (d) V = I x R

Q06. (c) 7.5

Q07. (b) Less than Least

Q08. (d) All of the above

Q09. (d) 10^{15}to 10^{17}

Q10. (c) More than Maximum

## One thought on “Electrical Circuit Theory Problems and Solutions”