#### Electrical engineering

• ( 1 ) With some initial change at t = 0+, a capacitot will act as

• 1) short circuit.
• 2) open circuit.
• 3) a voltage source.
• 4) a current source.
• Discussion in forum
Answer : 3) a voltage source.
Solution : At t = 0+, the capacitor starts charging to a particular voltage and acts as a voltage source.

discussion

Answer : 3) a voltage source.

• ( 2 ) If a circuit does not contain any source of energy or emf, it is known as

• 1) unilateral circuit.
• 2) bilateral circuit.
• 3) active network.
• 4) passive network.
• Discussion in forum
Solution : When a network does not contain any source of e.m.f., it is called passive network. A passive network consists of resistance, inductance or capacitance as passive element. A passive network does not contains any source of energy and the input port serve as load terminal. It may have output terminal.

discussion

• ( 3 ) Active element of electrical circuit is

• 1) voltage source.
• 2) current source.
• 3) both 1 & 2
• 4) none of these.
• Discussion in forum
Answer : 3) both 1 & 2
Solution : Active elements or sources - these are elements which can source electrical power; examples are voltage sources and current sources. They can be used to represent ideal batteries and power supplies

discussion

Answer : 3) both 1 & 2

• ( 4 ) The basic circuit elements are

• 1) R, L and C.
• 2) Vs, Is.
• 3) both 1 & 2
• 4) none of these.
• Discussion in forum
Answer : 1) R, L and C.
Solution : Resistance R, measured in ohms - produces a voltage proportional to the current flowing through the element. Relates voltage and current according to the relation dV = RdI.
Capacitance C, measured in farads - produces a current proportional to the rate of change of voltage across the element. Relates charge and voltage according to the relation dQ = CdV.
Inductance L, measured in henries - produces the magnetic flux proportional to the rate of change of current through the element. Relates flux and current according to the relation dφ = LdI

discussion

Answer : 1) R, L and C.

• ( 5 ) The linear circuit element is

• 1) capacitor.
• 2) inductor.
• 3) resistor.
• 4) all of above.
• Discussion in forum
Solution : The linear circuit element is resistor.

discussion

• ( 6 ) Clamping circuits are one which inserts

• 1) AC component in signal.
• 2) DC component in signal.
• 3) both AC and DC.
• 4) none of these.
• Discussion in forum
Answer : 2) DC component in signal.
Solution : Clamping circuits are one which inserts DC component in signal.

discussion

Answer : 2) DC component in signal.

• ( 7 ) A certain AC circuit has resistance of 10 Ω and impedance of 20 Ω. The phase angle of voltage and current of the circuit is

• 1) 60°.
• 2) 30°.
• 3) 90°.
• 4) 45°
• Discussion in forum
Solution : A certain AC circuit has resistance of 10 Ω and impedance of 20 Ω. The phase angle of voltage and current of the circuit is 60°.

discussion

• ( 8 ) An electrical circuit with 10 branches and 7 nodes will have

• 1) 10 loop equations.
• 2) 7 loop equations
• 3) 3 loop equations.
• 4) 4 loop equations.
• Discussion in forum
Answer : 4) 4 loop equations.
Solution : An electrical circuit with 10 branches and 7 nodes will have 4 loop equations.

discussion

Answer : 4) 4 loop equations.

• ( 9 ) Current is measured by a(n) __________.

• 1) voltmeter
• 2) ammeter
• 3) ohmmeter
• 4) electrometer
• Discussion in forum
Solution : Current is measured by a(n) ammeter.

discussion

• ( 10 ) What is the purpose of differential amplifier stage in internal circuit of Op-amp?

• 1) Low gain to differential mode signal
• 2) Cancel difference mode signal
• 3) Low gain to common mode signal
• 4) Cancel common mode signal
• Discussion in forum
Answer : 4) Cancel common mode signal
Solution : Cancel common mode signal

discussion

Answer : 4) Cancel common mode signal