ISO 9001:2015 Certified
V.V.P. Polytechnic, Solapur.
Department of Electronics & Telecommunication
Unit Test – II ( Model Answer Paper )
Class: SYEJ Course Code - 313325
Course: Circuits and Network Date: 13/11/2024
Marks: 30 Duration: 90 Min.
Instructions: 1) All questions are compulsory.
2) Assume suitable data if required.
Q. 1. Attempt any FIVE of following.
10 Marks
A) State Thevenin’s Theorem
Ans.- Statement of Thevenins Theorem –
“ Any network containing Active / Passive and one or more dependent/independent voltage or
current sources can be replaced by An Equivalent Network containing a voltage source ( Vth ) and
a series resistance ( Rth ).”
B) Define – 1) Active Network 2) Passive Network
Ans .- 1) Active Network :- If a network consists of an energy source ( Voltage or Current ) , then it is
Called as Active Network .
2) Passive Network :- If a network does not contain any energy source then it is called as the
Passive Network.
C) Write the Equation of Open Circuit Z parameter.
Ans. We Can obtain the Z Parameter by using two port voltages V1 & V2 in terms of two port currents
I1 & I2 ( where V1 and V2 are Dependent Variables & I1 & I2 are Independent Variables ).
The Basic equations of Z Parameters are as follows :-
V1 = Z11 . I1 + Z12 . I2
V2 = Z21 . I1 + Z22 . I2
Where Z11, Z12, Z21, Z22 are known as OPEN CIRCUIT Z Paramerters.
D) Write the Equation of Short Circuit Y parameters
Ans –
We Can obtain the Y Parameter by using two port currents I1 & I2 in terms of two port voltages
V1 & V2 ( where I1 and I2 are Dependent Variables & V1 & V2 are Independent Variables ).
The Basic equations of Y Parameters are as follows :-
I1 = Y11 . I1 + Y12 . I2
I2 = Y21 . I1 + Y22 . I2
Where Y11, Y12, Y21, Y22 are known as SHORT CIRCUIT Y Paramerters.
E) Define - 1) Lagging Phase Difference 2) Leading Phase Difference
Ans -
F ) State the meaning of Impedance Traingle.
Ans. –
G ) Write the ABCD Parameter for Two Port Network.
Ans : - We Can obtain the ABCD Parameter by , the voltage and current at one port is related to the
Voltage and current at the other port ( where V1 and I1 are considered as Dependent variabes
While V2 and I2 are considered as Independent Variables )
The Basic equations of ABCD Parameters are as follows :-
V1 = A. V2 - B. I2
I1 = C. V2 - D. I2
Q. 2. Attempt any FIVE of following.
20 Marks
(a) By using Thevenins Theorem , find Load Current ( I L ) for following figure –
Ans :-
(b) Derive Condition for Maximum Power Transferred from Source to Load –
Ans :-
(c) Define with their Formula - 1) Inductive Reactance 2) Capacitive Reactance
Ans.:-
(d) Define and State equation for : 1) Active Power
2) Reactive Power
3) Apparent Power
Ans :-
(e) Define Power Factor in 3 different ways and State Disadvantages of Low Power Factor
Ans.:-
(f) Write the equation of Resultant Impedance ( Z ) in R-L series circuit .
Ans. –
