1
GATE EE 2014 Set 3
MCQ (Single Correct Answer)
+2
-0.6
The mean thickness and variance of silicon steel laminations are 0.2 mm and 0.02
respectively. The varnish insulation is applied on both the sides of the laminations. The mean
thickness of one side insulation and its variance are 0.1 mm and 0.01 respectively. If the
transformer core is made using 100 such varnish coated laminations, the mean thickness and
variance of the core respectively are
2
GATE EE 2014 Set 3
MCQ (Single Correct Answer)
+2
-0.6
An open circuit test is performed on 50 Hz transformer, using variable frequency source and
keeping V/f ratio constant, to separate its eddy current and hysteresis losses. The variation of
core loss/frequency as function of frequency is shown in the figure
The hysteresis and eddy current losses of the transformer at 25 Hz respectively are
3
GATE EE 2014 Set 3
Numerical
+2
-0
The load shown in the figure absorbs 4 kW at a power factor of 0.89 lagging.
Assuming the transformer to be ideal, the value of the reactance X to improve the input
power factor to unity is ___________.
Your input ____
4
GATE EE 2014 Set 1
MCQ (Single Correct Answer)
+2
-0.6
The core loss of a single phase, 230/115 V, 50 Hz power transformer is measured from 230 V
side by feeding the primary (230 V side) from a variable voltage variable frequency source
while keeping the secondary open circuited. The core loss is measured to be 1050 W for
230 V, 50 Hz input. The core loss is again measured to be 500W for 138 V, 30 Hz input. The
hysteresis and eddy current losses of the transformer for 230 V, 50 Hz input are respectively.
Questions Asked from Transformers (Marks 2)
Number in Brackets after Paper Indicates No. of Questions
GATE EE 2023 (1)
GATE EE 2018 (2)
GATE EE 2017 Set 2 (1)
GATE EE 2017 Set 1 (1)
GATE EE 2016 Set 2 (2)
GATE EE 2016 Set 1 (3)
GATE EE 2015 Set 1 (2)
GATE EE 2015 Set 2 (3)
GATE EE 2014 Set 2 (1)
GATE EE 2014 Set 3 (4)
GATE EE 2014 Set 1 (1)
GATE EE 2013 (1)
GATE EE 2012 (1)
GATE EE 2010 (1)
GATE EE 2009 (6)
GATE EE 2008 (2)
GATE EE 2007 (1)
GATE EE 2006 (3)
GATE EE 2004 (3)
GATE EE 2003 (3)
GATE EE 2002 (1)
GATE EE 2001 (2)
GATE EE 2000 (1)
GATE EE 1999 (5)
GATE EE 1998 (1)
GATE EE 1997 (2)
GATE EE 1993 (1)
GATE EE Subjects
Electromagnetic Fields
Signals and Systems
Engineering Mathematics
General Aptitude
Power Electronics
Power System Analysis
Analog Electronics
Control Systems
Digital Electronics
Electrical Machines
Electric Circuits