A broadcast circute broadcasts at 300 m band. A condenser of capacitance 2.4 lµF is available. The value of the inductance required for resonant circuit is:
1.10-4 H
2.10-8 H
3.10-6 H
4.10-2 H
A rejector circuit is:
1.series resonant circuit
2.parallel resonant circuit
3.LCR circuit
4.None of the above
An ac ammeter connected in series in an ac circuit reads 5A. The peak value of current:
1. 5 A (b) (c)
2.5√2A
3.5√5 A
4.Zero
An acceptor circuit is :
1. series resonant circuit
2.parallel resonant circuit
3.LCR circuit
4.None of these
An electric circuit containing capacitor only suffers:
1.equal resistance for A.C. and D.C. (b)
2. Resistance of A.C. > Resistance of D.C.
3.Resistance for A.C. < Resistance of D.C.
4.offers infinite resistance for D.C.
An iron core transformer with a turns ratio of 8 : 1 has 120 V applied across the primary. The voltage across the
1.15 V
2.120 V
3.180
4.960 V
Energy dissipates in LCR circuit in :
1.L only
2.C only
3.R only
4.All the above
Faraday constant:
1.depends on the amount of the electrolyte
2.depends on the current in the electrolyte
3.is a universal constant
4. depends on the amount of charge passed through the electrolyte
In pure inductive circuit current
1.lags behind emf by π/2
2. leads the emf by π/2
3.lags behind emf by π
4. leads the emf by π
In series resonant circuit:
1.reactance is zero
2.current is zero
3.voltage is zero
4.None of the above
In series resonant circuit:
1.reactance is zero
2.current is zero
3.voltage is zero
4.None of the above
In series resonant circuit:
1.reactance is zero
2.current is zero
3.voltage is zero
4.None of the above
In the above problem, the value of the resistance of the coil Y is:
1.0.58 Ω
2. 5.8 Ω
3.1.16
4. 11.6 Ω
Power factor of an ac circuit is a measure of:
1.virtual power
2.power lost in the circuit
3.mean power
4.All the above
The average power dissipation in pure inductance or capacitance is: (a) 12 LI²
1.12 LI²
2.3/2 CV²
3.either (a) or (b)
4.zero
The current through an inductor of 1H is given by I = 3t sin t. The voltage across the inductor of 1 H is:
1.3 sin t + 3 cos t
2.3 sin t + 3t cos t
3.3 cos t + t sin t
4.3t cos t + sin t
The dimensional formula of impedance is;
1.[ML2T-2A-2]
2.ML2T-3A-2]
3.[ML2T-2A-1]
4. [ML2T-2A-3]
The dimensional formula of L/R is similar to that of:
1.requency
2.time
3.length
4.None of the above
The no. of turns in the primary coil of a transformer is 200 and the no. of turns in the secondary is 10. If 240 V a.c. is applied to primary, the output from the secondary
1.6 V
2.12 V
3.24 V
4.48 V
The no. of turns in the primary coil of a transformer is 200 and the no. of turns in the secondary is 10. If 240 V a.c. is applied to primary, the output from the secondary
1.6 V
2.12 V
3.24 V
4.48 V
The no. of turns in the primary coil of a transformer is 200 and the no. of turns in the secondary is 10. If 240 V a.c. is applied to primary, the output from the secondary
1.6 V
2.12 V
3.24 V
4.48 V
The phase difference b/w the A.C. and e.m.f. π2 Which of the following can not be the instituent of the circuit?
1.LC
2.L alone
3.C alone
4.RL
Transformer works on the principle of:
1.convertor
2.invertor
3.mutual induction
4.self-induction
Two coils X and Y are connected in series across a 240 V, 50 Hz supply. The resistance of X is 5Ω and inductance of Y is 0.02 H. The power consumed is 3 kW and the power factor is 0.75. The impedance of the circuit is:
1.0.144 Ω
2.1.44
3.14.4 Ω
4.144 Ω
What is the ratio of inductive and capacitance reactances in an ac circuit?
1. 1
2.ω²L
3.ω²LC
4.l
Which of the following effects is not shown in alternating current ?
1.Chemical effect
2.Magnetic effect
3.Heating current
4.All the above
Which of the following has dimensions different from the rest?
1. L/R
2.1RC
3.LC−−−√
4.RC