CU STRIP IS MORE CONDUCTIVE THEN GI STRIP.
SO LEAKAGE CURRENT OF X-MER GET LOW RESISTIVE PATH.

YES IT AFFECT IN FOME OF HEAT

The size and specification of bearing.
for exg BEARING No.6205 C3
6 For bearing type(deep groove ball bearing)
2 For Bearing diameater series
05 For size of Bearing 25 (05* factor 5)
C3 For clearence

% impedence is use to determine the max fault current the 
transformer is capable of delivering to a downstream short 
circuit. 
Fault current=FLC*100/%imp.
this fault current is use to cal fault MVA 
Fault MVA = 1.732 x fault current x V.

eg: If transformer of 2000kVA,5%imp having flc of around 
1200A is use to supply to a motor of same flc carrying 
capacity and if the voltage drop at transformer terminal is 
more than the permissible voltage drop (+- 10%)during 
stating of motor then the above transformer will be of 
lower rating hence we have to select the transformer rating 
higher than 2000kVA eg:-3000kVA (In other words transformer 
having higher SC current capability ).If voltage remain 
within the rated voltage of the motor then no oversizing of 
tranformer is required.

You have mentioned that u r fresher (EIE) but u didnt
mention which field ur searching i.e software or
instrumentation field.ok If u r searching for
instrumentation/electronic side some of these ques. asked freq.
1)Basic Electrical/Electronic ie what is ohms law,resistor
,capacitor,inductance etc and then transistors and thier
types,functions ,applications.Basic circuit diagram for
transistors,zener diode,triac,thyristor etc. well prepare
with basic electrical.Instrumentation amplifier ie opamp,555
timer,be sure to prepare digital electronics ie gate logic
2)Basic Instrumentation ie transducer,lvdt,rvdt,Thermocouple
,RTD etc and their working principle ,basic diagram
.temperatue sensors ,pressure sensors,what is strain guage etc.

Prepare basic of Electrical/Electronic/Instrumentation as a
 fresher thats enough .All The Best

Types of Controllers ie)closed loop control .open loop
controller,ratio controller.Then P,I,PI,PID controller,PLC
etc.refer Process control and Control Systems

if you see the voltage level between earth and neutral is 
approx 2to3v
this is becoz
earth is at potential zero
but neutral is not at exact zero
it is zero volt with respect to phase but is floating with 
respect to earth

approx 2to3v