Basic Electrical Engineering (3110005) MCQs

MCQs of DC Circuits

Showing 121 to 130 out of 137 Questions
121.
If the Voltage increases, what happens to dielectric strength?
(a) Increases
(b) Decreases
(c) Remains the same
(d) Becomes zero
Answer:

Option (a)

122.
Which medium has the highest dielectric strength?
(a) Water
(b) Mica
(c) Air
(d) Glass
Answer:

Option (c)

123.
A voltage source connected in series with a resistor can be converted to a?
(a) Current source in series with a resistor
(b) Current source in parallel with a resistor
(c) Voltage source in parallel with a resistor
(d) Cannot be modified
Answer:

Option (b)

124.
A current source connected in parallel with a resistor can be converted to a?
(a) Current source in series with a resistor
(b) Voltage source in series with a resistor
(c) Voltage source in parallel with a resistor
(d) Cannot be modified
Answer:

Option (b)

125.
A source transformation is_________
(a) Unilateral
(b) Bilateral
(c) Unique
(d) Cannot be determined
Answer:

Option (b)

126.
In source transformation________
(a) Voltage source remains the same
(b) Current sources remain the same
(c) Both voltage and current source remain the same
(d) Resistances remain the same
Answer:

Option (d)

127.
Which, among the following is the right expression for converting from delta to star?
(a) R1=Ra*Rb/(Ra+Rb+Rc), R2=Rb*Rc/(Ra+Rb+Rc), R3=Rc*Ra/(Ra+Rb+Rc)
(b) R1=Ra/(Ra+Rb+Rc), R2=Rb/(Ra+Rb+Rc), Rc=/(Ra+Rb+Rc)
(c) R1=Ra*Rb*Rc/(Ra+Rb+Rc), R2=Ra*Rb/(Ra+Rb+Rc), R3=Ra/(Ra+Rb+Rc)
(d) R1=Ra*Rb*Rc/(Ra+Rb+Rc), R2=Ra*Rb*Rc/(Ra+Rb+Rc), R3=Ra*Rb*Rc/(Ra+Rb+Rc)
Answer:

Option (a)

128.
Which, among the following is the correct expression for star-delta conversion?R1=Ra*Rb/(Ra+Rb+Rc), R2=Rb*Rc/(Ra+Rb+Rc), R3=Rc*Ra/(Ra+Rb+Rc)b)
(a) R1=Ra*Rb/(Ra+Rb+Rc), R2=Rb*Rc/(Ra+Rb+Rc), R3=Rc*Ra/(Ra+Rb+Rc)b)
(b) R1=Ra/(Ra+Rb+Rc), R2=Rb/(Ra+Rb+Rc), Rc=/(Ra+Rb+Rc)
(c) R1=Ra+Rb+Ra*Rb/Rc, R2=Rc+Rb+Rc*Rb/Ra, R3=Ra+Rc+Ra*Rc/Rb
(d) R1=Ra*Rb/Rc, R2=Rc*Rb/Ra, R3=Ra*Rc/Rb
Answer:

Option (c)

129.
Superposition theorem is valid for _________
(a) Linear systems
(b) Non-linear systems
(c) Both linear and non-linear systems
(d) Neither linear nor non-linear systems
Answer:

Option (a)

130.
In superposition theorem, when we consider the effect of one voltage source, all the other voltage sources are ____________
(a) Shorted
(b) Opened
(c) Removed
(d) Undisturbed
Answer:

Option (a)

Showing 121 to 130 out of 137 Questions