NET WORK THEORY PART-1

1. What is charge?
The charge is an electrical property of the atomic particles of which matter consists. The unit of charge is the coulomb.

2. Define current?
The flow of free electrons in a metal is called electric current. The unit of current is the ampere. Current (I) = Q/t, 
Where Q is total charge transferred & T is time required for transfer of charge.

3. What is voltage?
The potential difference between two points in an electric circuit called voltage. The unit of voltage is volt. It is represented by V OR v.
Voltage = W/Q = work done/Charge

4. Define power.
The rate of doing work of electrical energy or energy supplied per unit time is called the power. The power denoted by either P of p. It is measured in Watts. (W).
Power = work done in electric circuit/Time
P = dw/dt = dw/dq.dq/dt
P = VI

5. What is network?
Interconnection of two or more simple circuit elements is called an electric network.


6. Distinguish between a branch and a node of a circuit.
A part of the network which connects the various points of the network with one another is called a branch. A point at which two or more elements are jointed together is called node.

7. Distinguish between a mesh and a Loop of a circuit.
A mesh is a loop that does not contain other loops. All meshed are loops. But all loops are not meshes. A loop is any closed path of branches.

8. Define active and passive elements.
The sources of energy are called active element.
Example: voltage source, current source.
The element which stores or dissipates energy is called passive element.
Example: Resistor, Inductor, Capacitor.

9.Define unilateral and bilateral elements.
In unilateral element, voltage – current relation is not same for both the direction.
Example: Diode, Transistors.
In bilateral element, voltage – current relation is same for both the direction.
Example: Resistor

10. Define linear and non-linear elements.
If the element obeys superposition principle, then it is said to be linear elements.
Example: Resistor.
If the given network is not obeying superposition principle then it is said to be non linear elements.
Example: Transistor, Diode.

11.Define Lumped and distributed elements.
Physically separable elements are called Lumped element. Example : Resistor, Capacitor, Inductor.
A distributed element is one which is not separable for electrical purpose. Example : Transmission line has distributor resistance, capacitance and inductance.

12.How are the electrical energy sources classified?
The electrical energy sources are classified into:
1. Ideal voltage source
2. Ideal current source.

13. Define an ideal voltage source.
The voltage generated by the source does not vary with any circuit quantity. It is only a function of time.Such a source is called an ideal voltage source.

14. Define an ideal current source.
The current generated by the source does not vary with any circuit quantity. It is only a function of time.Such a source is called as an ideal current source.

15. What are independent source?
Independent sources are those in which, voltage and current are independent and are not affected byother part of the circuit.