Visvesvaraya Technological University (VTU) 2007 B.E Electrical and Electronics Engineering Model QP Basc Electrical set 2 - Question Paper

SET - II
MODEL ques. PAPER
06 ELE 15/25 - BASIC ELECTRICAL ENGINEERING
(Answer any five ques. by selecting at lowest 2 ques. from every part.)

PART – A
1a) Show that the equivalent resistance of 2 resistors connected in parallel is the ratio of the
product of those 2 resistances divided by the sum of those 2 resistance values. [Marks4]
b) discuss the Fleming’s rules as applied to the production of EMF and Torque. [Marks8 ]
c) issue on electro – magnetism / D.C. circuits. [Marks8]

2a) With usual notations show that the avg. power consumed by a pure capacitor is zero. [Marks6 ]
b) With reference to an a.c circuit, differentiate ranging from
i) Phase and Phase difference, ii) Reactance and Impedance,
iii) lag and lead power factors. [Marks six ]
c) issue on single phase a.c circuit. [Marks8]

3a) find the relationship ranging from the line and phase volumes of balanced Star or
Delta loads. [Marks8]
b) In the course of measurement of power in 3 phase circuits the watt meter

readings are related as follows. obtain the power factor when,
i) W1 = W2, ii) W1 = 2W2, iii) W1 = 0. six
c) issue on 3 phase circuit. [Marks six ]

4a) With a neat sketch discuss the working of a single phase energy meter [Marks8 ]
b) Write a brief note on fuse. [Marks4 ]
c) discuss what is Earthing and with a neat sketch discuss the plate Earthing [Marks8 ]
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PART – B

5a) With usual notation derive an expression for the induced E.M.F of a D.C. machine [Marks6 ]
b) Draw the typical Speed - load characteristics of a D.C. series motor and comment on

its shape. Mention its practical applications. [Marks6 ]
c) issue on D.C. Generator or D.C. Motor. [Marks eight ]

6a) With usual notations derive an expression for the induced EMF in a single phase
Transformer and describe the term transformation ratio. [Marks eight ]
b) List out the different losses in a transformer and discuss how they vary with load and
how they are minimized. [Marks6 ]
c) issue on transformer. [Marks6 ]

7a) discuss the Salient and Non Salient pole generators and where they are preferred. [Marks6 ]
*b) List out the different losses in an ac generator and how its efficiency is estimated. [Marks6]
c) issue on alternator. [Marks 8]

8a) describe the term ‘slip’ in an Induction motor and discuss its importance. [Marks six [Marks
b) discuss the necessity of a starter for an Induction motor. [Marks4]
c) issue on Induction motor. [Marks10]

Earning:   Approval pending.