EC
Engineering Classroom
by Himalay Sen

Exams

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Board Questions

Access past board exam questions organized by year and subject to help you understand patterns, improve preparation, and boost your exam performance.

MCQ
5463. A fuse is a--
protective device
current limiting device
current controling device
none of the above
ব্যাখ্যা: ব্যাখ্যাঃ in electronic and electrical engineering, a fuse is an electrical safety or protective device, that operates provide overcurrent protection of an electrical circuit
5465. Primary winding of CT is connected--
In series with the load
In parallel with the load
Between line and neutral
Both (a) and (b)
ব্যাখ্যা: ব্যাখ্যা: The primary winding of the current transformer(CT) is connected in series with the transmission line whose current is to be measured where the potential transformer (PT) is connected in parallel with the line
5468. Substation-এ কোন ধরনের ট্রান্সফর্মার ব্যবহৃত হয়?
Step up
Step down
Both ক&খ
None
ব্যাখ্যা: ব্যাখ্যা: উচ্চ ভোল্টেজকে সাবস্টেশনে স্টেপ ডাউন ট্রান্সফর্মারের সাহায্যে গ্রাহক উপযোগী করে বিতরণ করা হয়।
5470. A permeable substance is one--
Which is a good conductor
Which is a band conductor
Which is a strong magnet
Through which the magnetic lines of force can pass very easily
5472. The relay operation coil is supplied through-
fuse
power transformer
current transformer
none
ব্যাখ্যা: ব্যাখ্যা: The relay operating coil is supplied through current treansformer. Current transformer is used to measure the current as the indication for relay.
5473. An isolator is designed to open a circuit--
full load
normal condition
no load
all of the above
ব্যাখ্যা: ব্যাখ্যা : An isolator is designed to open a circuit under no load Its main purpose is to isolate one portion of the circsil from the other and is not intended to be opened while current is flowing in the line
5474. Under normal operating conditions, the contacts of the circuit breaker remain-
closed
semiclosed
open
none of the above
ব্যাখ্যা: ব্যাখ্যা: Under normal operating conditions, the contacts the circuit breaker remain closed. When any fault occart the contact is opened.
5476. Most faults occurring in the field are in-
CTs and PTS
switchgears
overhead lines
cables
ব্যাখ্যা: ব্যাখ্যা: Most faults occuring overhead lines. Because in raining day, there is more probability to occur fault. Leakage current and short circuit current frequently occured an raining day
5477. Inverse time current relays are used for the protection of-
Feeders
Transformers
Alternators
Both A and B
ব্যাখ্যা: ব্যাখ্যা: Inverse time current relays, operating time is inversely changed with current So, hich current will operate over current relay faster than lower ones. It is used feeders and transformers
5480. A circuit breaker is essentially-
an automatic switch
a manual switch
a high-lightning arrester
none of the above
ব্যাখ্যা: ব্যাখ্যা: A circuit breaker is an automatically operated electrical switch designed to protect an electrical circuit from damage caused by excess current from an overload or short circuit.