GROUP OFInstitutions JRE SCHOOL OF ENGINEERING·

Assignment - 1DC Network Theorems

Date of IssueClass 27/09/2012B. Tech (Section B & C)

Date of SubmissionSubject 01110//2012Electrical Engineering (EEE-101l201)

1. Briefly Explain the following(i) Maxwell's Mesh Current Analysis method(ii) Nodal Analysis(iii) Superposition Theorem(iv) Thevenin Theorem(v) Norton Theorem(vi) Maximum Power Transfer Theorem

2. Find the current I, and Vx in the following circuit using (i) Maxwell's MeshCurrent Analysis method (ii) Nodal Analysis (iii) Superposition Theorem (iv)Thevenin Theorem (v) Norton Theorem

I. 20

+

90"20 V.

120V " 9020 V.

Fig. 2(~) Fig.2(b)

r,2

IOV

2V J--,I.,_'. __Flg.2(e} Fig.2(d). ....

*****

--+-

Signature of HODDa.-

Signature of FacultyDate'.,

---- ---46..'j Page

..---. ~--+-

~=---_EI" __-••••.--===-•. 1 ~_...... . .-..-.....------ '~~''''''''''''i-~'!'~~~--- .--

VGROUP OfInstitutions JRE SCHOOL OF ENGINEERING

Assignment - 2DC Network Theorems

Class B. Tech (Section B & C) Date of Issue 27/09/2012

Subject Electrical Engineering (EEE-101l201) Date of Submission 011101/2012

1. Three resistances RA' RBand Rc are connected in star fashion(Fig. Q1) at nodesA, B and C of electric circuit. Determine the value of equivalent delta connectedresistances to be put between points A, B and C.

('

Fig. Q1 Fig. Q22. Three resistances RAB,RBCand RCAare connected in delta fashion (Fig Q2) at

nodes A, B and C of an electric circuit. Determine the values of equivalent starconnected resistances to be put between points A, B and C.

3. Find the value of current I in Fig. Q3 using(i) Star/Delta transformation method and(ii) Maxwell's Mesh Current analysis

a.'U~-<*~':'~l·t .io~-.I

I ;jl'r.-- j22"': i

fu.--QL-4. Explain the following terms:

(i) Active and Passive circuit elements(ii) Linear and non-linear network(iii) Unilateral and Bilateral elements(iv) Lumped and Distributed parameters

5. In the Fig. Q4, Calculate the value ofR which will allow the maximum powerdissipation. Also calculate the maximum power.

2

Fig. Q4 _

Signature QfHODDate

_~jgnature of Facmty~Date

47 [Paie --.~.--~H--- -

---~ .---,.-==:------

+-. ~ --.~ __ -L...:..~

~

-<-. ---- --- -

~.-=--I••••• 'E.'~ ~----.~______ ~......-i::..- _

~'~__ ~I---~0'. "'-''''

JRE SCHOOL OF ENGINEERING

Class B. Tech (Section B & C) Date of Issue 27/09/2012

Subject Electrical Engineering (EEE-101/201) Date of Subm ission 08/1012012

Assignment - 3Fundamentals of AC

I. An ac sinusoidal current has RMS value of 40A at SOHz frequency. Writeexpression of instantaneous current and obtain its value at 0.002second afterpassing through maximum value.

2. An alternating voltage is given by v= 141.4sin314t. Find (i) frequency (ii) rmsvalue (iii) average value (iv) The instantaneous value of the voltage when t is3ms. (Y) time taken for the voltage to reach 100Y for the first time after passingthrough zero val ue.

3. An alternating voltage is v=l OOsinl 00t. Find (i) Amplitude (ii) Time-period andfrequency (iii) Angular velocity (iv) form factor (v) Peak factor

-I-. Calculate average and rrns value of periodic wave as shown in figure.

S. Two alternating currents represented by equations II=7sinwt and i2=10sin(wt+n/3). Find equation for resultant current and its rills value.

6. Currents flowing in the three branches of an ac parallel circuit are i1=20sinwt,i2=2Ssin (wt-n/6) and i3=lSsin (wt+n/6). Determine the total current drawn fromsupply.

7. Three sinusoidal voltages are given byVI= 10sin440t, v2=10~2 sin (440t-4So) and v3=20cos440t

Determine(i) Expression for (a) V=VI+V2+V3(b) V=VI-V2-V3

(ii) Frequency and rms value of part (a) and (b)

*****

48 I

JRE SCHOOL OF ENGINEERINGAssignment - 4

Fundamentals of AC-

Class B. Tech (Section B & C) Date of Issue 27/09/2012

Subject Electrical Engineering (EEE-101/201) Date of Subm ission 08/10/2012'--

1. An alternating current of I.SA flows in a circuit when applied voltage is300V.the power consumed is 22SW.find resistance and reactance of the circuit.

2. In a purely inductive circuit, prove that from first principles, that the current lagsbehind the apply voltage by quarter of cycle and also show that average powerdemand is zero.

3. The equation of alternating current is i= 42.42sin628t.Detennine (i)it'smaximum value (ii) frequency (iii) average value (iv) rms value (v) form factor

4. A load having impedance of (I +j I) D is connected to an ac voltage representedas v= 20V2cos (CDt+10°) volt. Find (i) current in load, expressed in the form of i= 1111sin (CDt+<D0)(ii) real power consumed by load.

5. An ac voltage e (t) =141.4sinI20t is applied to a series R-C circuit. The currentthrough the circuit is obtained as i(t)=14.14sin 120t+ 7.07cos(120t+ 30°).Determine (i) value of resistance and capacitance (ii) power factor (iii) powerdeveloped by the source

6. A 100V. 80W lamp is to be operated on 230V, 50Hz ac. calculate the inductanceand pure resistance to be connected in series with the lamp. Lamp can be takenas pure resistance.

7. Two impedances ZI= (10+j5) and Z2= (8+j6) are connected in parallel across avoltage of V= 200+jO. Calculate the circuit current, power factor and reactivepower.

8. A two element series circuit is connected across an ac source v= 300cos(314t+ 20°) volt. The current drawn is 15 cos (314t-100) ampere. Determinethe circuit impedances magnitude and phase angle. What is average powerdrawn?

9. A coil takes 4A when connected to 24V de supply. If this coil is connected to40V. 50Hz ac supply then same amount of power is consumed. Explain whydifferent voltages required for same power consumption are. Calculateinductance ofthe coil and the phase angle between voltage and current.

10. A series RLC circuit has R=I 0 D, L=O.I Hand C= 8~lF. Determine(i) resonant frequency (ii) Q-factor of the circuit at resonance (iii) half power

frequencies

Signature of HODDate

Signature of FacultyDate

49 I