# ONLINE MCQ EE-ELECTROMAGNETIC INDUCTION 1

Q1. Air-core coils are practically free from
A.  hysteresis losses
B.  eddy current losses
C.  both (a) and (b)
D.  none of the above
 \$(document).ready(function(){ \$(‘#loaddata2100’).click(function(){ qid2100=\$(‘#qid2100’).val(); section2100=\$(‘#section2100’).val(); type2100=\$(‘#type2100’).val(); subtype2100=\$(‘#subtype2100’).val(); \$.post(‘../../fav’,{ qid:qid2100, section: section2100, type: type2100, subtype: subtype2100 },function(ajaxresult){ \$(‘#getrequest2100’).html(ajaxresult); qid2100=\$(‘#qid2100’).val(”); section2100=\$(‘#section2100’).val(”); type2100=\$(‘#type2100’).val(”); subtype2100=\$(‘#subtype2100’).val(”); }); }); }); Explanation:- Answer : C

Q2. For a purely inductive circuit which of
the following is true ?
A.  Apparent power is zero
B.  Relative power is zero
C.  Actual power of the circuit is zero
D.  Any capacitance even if present in
the circuit will not be charged
 \$(document).ready(function(){ \$(‘#loaddata2101’).click(function(){ qid2101=\$(‘#qid2101’).val(); section2101=\$(‘#section2101’).val(); type2101=\$(‘#type2101’).val(); subtype2101=\$(‘#subtype2101’).val(); \$.post(‘../../fav’,{ qid:qid2101, section: section2101, type: type2101, subtype: subtype2101 },function(ajaxresult){ \$(‘#getrequest2101’).html(ajaxresult); qid2101=\$(‘#qid2101’).val(”); section2101=\$(‘#section2101’).val(”); type2101=\$(‘#type2101’).val(”); subtype2101=\$(‘#subtype2101’).val(”); }); }); }); Explanation:- Answer : C

Q3. Find the force acting on a conductor 3m
long carrying a current of 50 amperes
at right angles to a magnetic field
having a flux density of 0.67 tesla.
A.  100 N
B.  400 N
C.  600 N
D.  1000 N
 \$(document).ready(function(){ \$(‘#loaddata2102’).click(function(){ qid2102=\$(‘#qid2102’).val(); section2102=\$(‘#section2102’).val(); type2102=\$(‘#type2102’).val(); subtype2102=\$(‘#subtype2102’).val(); \$.post(‘../../fav’,{ qid:qid2102, section: section2102, type: type2102, subtype: subtype2102 },function(ajaxresult){ \$(‘#getrequest2102’).html(ajaxresult); qid2102=\$(‘#qid2102’).val(”); section2102=\$(‘#section2102’).val(”); type2102=\$(‘#type2102’).val(”); subtype2102=\$(‘#subtype2102’).val(”); }); }); }); Explanation:- Answer : A

Q4. Current changing from 8 A to 12 A in
one second induced 20 volts in a coil.
The value of inductance is
A.  5 mH
B.  10 mH
C.  5 H
D.  10 H
 \$(document).ready(function(){ \$(‘#loaddata2103’).click(function(){ qid2103=\$(‘#qid2103’).val(); section2103=\$(‘#section2103’).val(); type2103=\$(‘#type2103’).val(); subtype2103=\$(‘#subtype2103’).val(); \$.post(‘../../fav’,{ qid:qid2103, section: section2103, type: type2103, subtype: subtype2103 },function(ajaxresult){ \$(‘#getrequest2103’).html(ajaxresult); qid2103=\$(‘#qid2103’).val(”); section2103=\$(‘#section2103’).val(”); type2103=\$(‘#type2103’).val(”); subtype2103=\$(‘#subtype2103’).val(”); }); }); }); Explanation:- Answer : C

Q5. Which of the following circuit element
stores energy in the electromagnetic
field?
A.  Inductance
B.  Condenser
C.  Variable resistor
D.  Resistance
 \$(document).ready(function(){ \$(‘#loaddata2104’).click(function(){ qid2104=\$(‘#qid2104’).val(); section2104=\$(‘#section2104’).val(); type2104=\$(‘#type2104’).val(); subtype2104=\$(‘#subtype2104’).val(); \$.post(‘../../fav’,{ qid:qid2104, section: section2104, type: type2104, subtype: subtype2104 },function(ajaxresult){ \$(‘#getrequest2104’).html(ajaxresult); qid2104=\$(‘#qid2104’).val(”); section2104=\$(‘#section2104’).val(”); type2104=\$(‘#type2104’).val(”); subtype2104=\$(‘#subtype2104’).val(”); }); }); }); Explanation:- Answer : A

Q6. The magnitude of the induced e.m.f. in
a conductor depends on the
A.  flux density of the magnetic field
B.  amount of flux cut
D.  rate of change of flux-linkages
 \$(document).ready(function(){ \$(‘#loaddata2105’).click(function(){ qid2105=\$(‘#qid2105’).val(); section2105=\$(‘#section2105’).val(); type2105=\$(‘#type2105’).val(); subtype2105=\$(‘#subtype2105’).val(); \$.post(‘../../fav’,{ qid:qid2105, section: section2105, type: type2105, subtype: subtype2105 },function(ajaxresult){ \$(‘#getrequest2105’).html(ajaxresult); qid2105=\$(‘#qid2105’).val(”); section2105=\$(‘#section2105’).val(”); type2105=\$(‘#type2105’).val(”); subtype2105=\$(‘#subtype2105’).val(”); }); }); }); Explanation:- Answer : D

Q7. Which of the following is unit of inductance?
A.  Ohm
B.  Henry
C.  Ampere turns
D.  Webers/metre
 \$(document).ready(function(){ \$(‘#loaddata2106’).click(function(){ qid2106=\$(‘#qid2106’).val(); section2106=\$(‘#section2106’).val(); type2106=\$(‘#type2106’).val(); subtype2106=\$(‘#subtype2106’).val(); \$.post(‘../../fav’,{ qid:qid2106, section: section2106, type: type2106, subtype: subtype2106 },function(ajaxresult){ \$(‘#getrequest2106’).html(ajaxresult); qid2106=\$(‘#qid2106’).val(”); section2106=\$(‘#section2106’).val(”); type2106=\$(‘#type2106’).val(”); subtype2106=\$(‘#subtype2106’).val(”); }); }); }); Explanation:- Answer : B

Q8. A coil with negligible resistance has 50
V across it with 10 mA. The inductive
reactance is
A.  50 ohms
B.  500 ohms
C.  1000 ohms
D.  5000 ohms
 \$(document).ready(function(){ \$(‘#loaddata2107’).click(function(){ qid2107=\$(‘#qid2107’).val(); section2107=\$(‘#section2107’).val(); type2107=\$(‘#type2107’).val(); subtype2107=\$(‘#subtype2107’).val(); \$.post(‘../../fav’,{ qid:qid2107, section: section2107, type: type2107, subtype: subtype2107 },function(ajaxresult){ \$(‘#getrequest2107’).html(ajaxresult); qid2107=\$(‘#qid2107’).val(”); section2107=\$(‘#section2107’).val(”); type2107=\$(‘#type2107’).val(”); subtype2107=\$(‘#subtype2107’).val(”); }); }); }); Explanation:- Answer : D

Q9. Which circuit element(s) will oppose
the change in circuit current?
A.  Resistance only
B.  Inductance only
C.  Capacitance only
D.  Inductance and capacitance
 \$(document).ready(function(){ \$(‘#loaddata2108’).click(function(){ qid2108=\$(‘#qid2108’).val(); section2108=\$(‘#section2108’).val(); type2108=\$(‘#type2108’).val(); subtype2108=\$(‘#subtype2108’).val(); \$.post(‘../../fav’,{ qid:qid2108, section: section2108, type: type2108, subtype: subtype2108 },function(ajaxresult){ \$(‘#getrequest2108’).html(ajaxresult); qid2108=\$(‘#qid2108’).val(”); section2108=\$(‘#section2108’).val(”); type2108=\$(‘#type2108’).val(”); subtype2108=\$(‘#subtype2108’).val(”); }); }); }); Explanation:- Answer : B

Q10. The inductance of a coil will increase
under all the following conditions
except
A.  when more length for the same
number of turns is provided
B.  when the number of turns of the coil
increase
C.  when more area for each turn is
provided