Multiple Choice Questions with Ans on Electronics & Communication(PDF)
1. The iron core is used to —of the transformer.
a)reduce core losses
b)provide tight magnetic coupling (Answer)
c)reduce cost
d)provide long live
2. The voltage per turn of the primary of a transformer is —the voltage per turn of the secondary.
a)more than
b)less than
c)same as (Answer)
d)none of above
3. The no-load p.f of transformer is small, because
a)magnetizing component of I0 is large (Answer)
b)magnetizing component of I0 is small
c)Iron loss component of I0 is large
d)none of above
4. The effect of leakage flux in a transformer is to—
a)cause voltage drop in the windings (Answer)
b)increase copper loss
c)decrease copper loss
d)none of above
5. When load in a transformer is increased, the eddy current—
a)increased
b)decreased
c)remain unchanged (Answer)
d)none of above
6. An induction motor is preferred to a d.c motor, because
a)has simple and rugged construction (Answer)
b)provides high starching
c)torque provide fine speed control
d)all of above
7. In a 3- phase induction motor, the rotor speed is —- the Synchronous speed.
a)greater then
b)smaller than (Answer)
c)equal to all
d)of above
8. The induction motor has lagging power factor during
a)starting only
b)running only
c)both starting and operation (Answer)
d)none of above
9. A single phase induction motor employs—rotor
a)wound
b)squirrel cage (Answer)
b)either squirrel cage or wound
c)none of above
10. The electrons in the last orbit of an atom are called–
a) free electrons (Answer)
b) valence electrons
c) bound electron
d) All of Above
11. Insulator have—temperature co-efficient of resistance.
a) positive
b) zero
c) negative (Answer)
d) All of Above
12. Which one of the following is the best conductor of electricity?
a) Silver (Answer)
b) Gold
c) copper
d) carbon
13. Two equal resistances are connected in series across a certain supply.
If the resistances are now connected in parallel. The power produced will become—
a) two times
b)one half
c)four times (Answer)
d)remain same
14. A heater coil rated at 1000W, 220V is connected to 110v line. Power consumed is—
a)250 W (Answer)
b)100W
c)500W
d)110W
15. An alternating voltage is given by v = 20sin314t, the frequency of the alternating voltage is
a)25Hz
b)50Hz (Answer)
c)100Hz
d)60Hz
16. An alternating voltage is given by v= 200sin 314t. its r.m.s valve will be
a)141.4V (Answer)
b)314V
c)200V
d)100V
17. The form factor of a sinusoidal wave is–
a)1.41
b)1.11 (Answer)
d)1 0.5
18. The form factor of a—wave is 1
a)sinusoidal
b)triangular
c)square (Answer)
d)saw tooth
19. An current of 5 A is same as –
a)5 W / C.
b) 5 C / Sec. (Answer)
c) 5 V / C.
d)5 J / C.
20. A wattmeter indicates—power.
a)active (Answer)
b)apparent
c)reactive
d)none of above
21. At series resonance condition, the voltage across L or C is—-
a)much more than applied voltage (Answer)
b)less than applied voltage
c)equal to applied voltage
d)equal to voltage across R
22. An ammeter is —– instrument.
a)an integrating (Answer)
b)an indicating
c)a recording
d)None of above.
23. PMMC instrument can be used for……
a)a.c work only (Answer)
b)d.c work only both
c)a.c and d.c work
d)None of above.
24. An electric pyrometer is an instrument used to measure.
a)Phase
b)Temperature (Answer)
c)Frequency
d)Power
25. The real working part of a d.c machine is the—-
a)Armature winding (Answer)
b)commentator
c)field winding
d)brushes
26. A 4- pole d.c machine has —–magnetic circuits
a)2
b)4 (Answer)
c)8
d)1
27. The commutator of a d.c generator acts as –
a)a rectifier (Answer)
b)an amplifier
c)a load
d)none of above
28. The speed of a—motor is practically constant.
a)series
b)shunt (Answer)
c)cumulatively compound
d)deferentially compound
29. In d.c motor carbon brushes are preferable to copper brushes because-
a)the have lower resistance
b)the have longer life.
c)the reduce sparking (Answer)
d)none of above
30. The back emf in d.c motor—-
a)opposes the applied voltage
b)aids the applied voltage (Answer)
c)aids the armature Current
d)none of above
31. The load factor is generally-
a)more than 1
b)less than 1 (Answer)
c)equal to 1
d)equal to 2
32. As a matter of economy, voltage for Power transmission line should be-
a)high (Answer)
b)low
d)medium
33. The economic size of a conductor is determined by–
a)ohm’s law
b)Kelvin’s law (Answer)
c)resistance law
d)none of above
34. A semiconductor generally has—- valence electrons
a)1
b)2
c)3
d)4 (Answer)
35. When a pure semiconductor is heated, its resistance will—
a)goes up
b)goes down (Answer)
c)remain same none
d)of above
36. নেপালের নতুন সংবিধান কার্যকর হয় কবে থেকে?
a)২০ সেপ্টেম্বর ২০১৫ (Answer)
b)১ লা সেপ্টেম্বর ২০১৫
c)১০ সেপ্টেম্বর ২০১৫
d)১১ সেপ্টেম্বর ২০১৫
37. ‘জাতীয় কন্যা শিশু দিবস’ কবে?
a)৩ সেপ্টেম্বর
b)১ সেপ্টেম্বর
c)১০ সেপ্টেম্বর
d)৩০ সেপ্টেম্বর (Answer)
38. চর্যাপদের আবিস্কারের সাল কোনটি?
a)১৯০৫
b)১৯১৩
c)১৯০১
d)১৯০৭ (Answer)
39. ‘সবকটা জানালা খুলে দাও না’ গানটির গীতিকার কে?
a)নজরুল ইসলাম বাবু (Answer)
b)আবদুল গাফফার চৌধুরী
c)কাজী নজরুল ইসলাম
d)কবীর বকুল
40. ‘অ্যাবেল পুরস্কার’ নিচের কোন বিষয়ের সাথে সম্পর্কিত?
a)রসায়ন বিজ্ঞান
b)পদার্থি বিজ্ঞান
c)চিকিৎসা বিজ্ঞান
d)গণিত (Answer)
41. টাকায় ৫ টি দরে লেবু ক্রয় করে টাকায় কয়টা দরে বিক্রয় করলে ২৫% লাভ হবে?
a)৫ টা
b)৬ টা
c)৪ টা (Answer)
d)২ টা
42. যদি y একটি মৌলিক সংখ্যা তবে y এর বর্গমূল একটি…
a)মূলদ সংখ্যা
b)অমূলদ সংখ্যা (Answer)
c)পূর্ণ সংখ্যা
d)স্বাভাবিক সংখ্যা
43. ৯ জন লোক যদি একটি কাজ ৩ দিনে করে তবে কতজন লোক ঐ কাজটি ৯ দিনে করতে পারবে?
a)৯ জন
b)৪ জন
c)৩ জন (Answer)
d)১৮ জন
44. ‘Linguistics’ বাংলা পরিভাষা কী?
a)ভাষাবিজ্ঞান (Answer)
b)শব্দবিজ্ঞান
c)চলতি সম্পত্তি
d)কোনটি নহে
45. কোন রাজবংশের আমলে চর্যাপদ রচনা শুরু হয়?
a)তুঘল
b)পাল (Answer)
c)সেন
d)তুর্কি
46. ‘লাজ’ শব্দটি কোন পদ?
a)বিশেষণ
b)বিশেষ্য (Answer)
c)সর্বনাম
d)ক্রিয়া বিশেষণ
47. Which is Abstract noun?
a)Height (Answer)
b)Man
c)Long
d)Jury
48. She is good ….. lawn tennis.
a)at (Answer)
b)on
c)in
d)for
49. The word ‘revoke’ means-
a)to go back
b)to call back (Answer)
c)to call in
d)to move
50. Which is not computer network?
a)CAN (Answer)
b)LAN
c)MAN
d)WAN
2 Comments