NODIA AND COMPANY. Model Test Paper - I GATE Electrical & Electronic Measurement. Copyright By Publishers

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1 No part of this publication may be reproduced or distributed in any form or any means, electronic, mechanical, photocopying, or otherwise without the prior permission of the author. Model Test Paper - I GATE Copyright By Publishers Information contained in this book has been obtained by authors, from sources believes to be reliable. However, neither Nodia nor its authors guarantee the accuracy or completeness of any information herein, and Nodia nor its authors shall be responsible for any error, omissions, or damages arising out of use of this information. This book is published with the understanding that Nodia and its authors are supplying information but are not attempting to render engineering or other professional services. NODIA AND COMPANY B-8, Dhanshree Tower Ist, Central Spine, Vidyadhar Nagar, Jaipur Ph : enquiry@nodia.co.in Printed by Nodia and Company, Jaipur

2 Q. 1 - Q. 5 carry one mark each. Q.1 The maximum percentage error in the sum of two voltage measurements when V = 100 V! 1% andv = 80 V! 5% is 1 2 (A)! 4% (B)!2. 8% (C)! 6% (D)!3% Q.2 Torque/Weight ratio of an instrument indicates (A) Selectivity (C) Fidelity (B) Accuracy (D) Sensitivity Q.3 The range of an electrostatic voltmeter can be extended by using (A) a capacitor in series with the voltmeter whose capacitance is greater than the capacitance of the voltmeter. (B) a capacitor in series with the voltmeter whose capacitance is smaller than the capacitance of the voltmeter. (C) a resistor in series with the voltmeter. (D) an inductor in series with the voltmeter. Q.4 Which of the following ammeter will be used to measure alternating currents only (A) electrodynamic type (B) permanent magnet type (C) induction type (D) moving type Q.5 Maxwell s inductance-capacitance bridge is used for measurement of inductance of (A) low Q coils only (C) high Q coils only (B) medium Q coils only (D) low and medium Q coils

3 Q. 6 - Q. 15 carry two marks each. Q.6 A multi-range voltmeter is shown in the figure with full-scale deflection current Ifsd = 50 ma and meter resistance of 1kW. What are the values of resistances R 1, R 2 and R 3 respectively? (A) 100 kw, 200 kw, 1000 kw (B) 101 kw, 201 kw, 1001 kw (C) 99 kw, 199 kw, 999 kw (D) 5kW, 10kW, 50kW Q.7 A voltmeter, having a sensitivity of 1 kw / V, connected across an unknown resistance in series with a milliammeter, reads 80 V on 150 V scale. If the milliammeter reads 10 ma, the error due to loading effect of voltmeter would be (A) 72% (B) 4.6% (C) 5.3% (D) 38.65% Q.8 A voltmeter reading 70 V on its 100 V range and an ammeter reading 80 ma on its 150 ma range are used to determine the power dissipated in a resistor. Both these instruments are guaranteed to be accurate within! 15. %, at full scale deflection. The limiting error of the power is (A) 3.00% (B) 4.956% (C) 6.266% (D) 2.143%

4 Q.9 The time/div and voltage/div axes of an oscilloscope have been erased. A student connects a 1 khz, 5 V p-p square wave calibration pulse to channel-1 of the scope and observes the screen to be as shown in the upper trace of the figure. An unknown signal is connected to channel-2 (lower trace) of the scope. It the time/div and V/div on both channels are the same, the amplitude (p-p) and period of the unknown signal are respectively (A) 5 V, 1 ms (C) 7.5 V, 2 ms (B) 5 V, 2 ms (D) 10 V, 1 ms Q.10 A ring core transformer with ratio 1000/5 A is operating at full primary current and with a secondary burden of non-inductive resistance of 1 W. The exciting current is 1 A at a power factor of 0.4, what is the phase angle error? (A) c (B) c (C) c (D) c Q.11 The ac bridge shown in the figure is used to measure an impedance. The bridge is assumed to be in balanced condition. The impedance Z is equivalent to (A) series combination of a resistor of 1kW and a inductor of 1mH

5 (B) parallel combination of a resistor of 100 W and an inductor of 1mH (C) series combination of a resistor of 10 kw and a capacitor of 100 pf (D) parallel combination of a resistor of 1kW and an inductor of 1mH Numerical Answer Questions Q.12 A PMMC voltmeter is connected across a series combination of DC voltage source V 1 = 2 V and AC voltage source V2 () t = 3 sin(4) t V. The meter reads Q.13 A reading of 120 is obtained when standard inductor was connected in the circuit of a Q-meter and the variable capacitor is adjusted to value of 300 pf. A lossless capacitor of unknown value C x is then connected in parallel with the variable capacitor and the same reading was obtained when the variable capacitor is readjusted to a value of 200 pf. The value of C x in pf is Common Data Questions Common Data for Questions 14 and 15: The value of an unknown capacitor which consists of a pure capacitance C s in series with a resistance R s is measured by the bridge shown in figure. The bridge is balanced at a frequency of 100 Hz. Q.14 What are the values of C s and R s respectively? (A) mf, 85 W (B) mf, 85 (C) mf, W (D) mf, W W

6 Q.15 What is the dissipation factor of the unknown capacitor? (A) 667. # 10-3 (B) # 10-3 (C) 785. # 10-3 (D) # 10-3 END OF THE QUESTION PAPER For detailed Solutions of this test paper please mail to enquiry@nodia.co.in. Please mention your Name, College, Graduating Year and GATE Registration Number in the mail.