A wire of resistance R is coiled inductively so that its inductance is L. The impedance of the coil at a frequency of f is_______________?

A. (r+2πfl)
B. R+1/2πfl
C. (r2+f2l2)
D. (r2+4π2f2l2)

Ammeter connected in an AC circuit measures______________?

A. The exact value of the current
B. Rms value of the current
C. The net value of the current
D. The peak value of the current

When a pure inductor of inductance L and a pure capacitor of capacitance C are connected in parallel to a sinusoidal potential difference V the potential difference across both L & C will be_______________?

A. Same
B. Different
C. At l will be more than at c
D. At l will be less than at c

What is the self-inductance of a coil in which an induced emf of 2V is set up when the current changes at the rate of 4 As-1 ?

A. 0.5 mh
B. 0.5h
C. 2.0h
D. 8.0h

The frequency of a circuit consisting of a capacitance C and a resistor R is________________?

A. C/r
B. R/c
C. 1/rc
D. 1/ 2rc

A 10Ω electric heater is connected to a 220V 50Hz mains supply. What is the peak value of the potential difference across the heater element ?

A. 220v
B. 220/ 2v
C. 110v
D. 220 √2v

A choke is used as a resistance in_________________?

A. Dc circuit
B. Ac circuits
C. Both ac and dc circuit
D. Full wave rectifier circuit

Galvanometer is a very sensitive device with______________________?

A. Very low damping
B. Very high damping
C. No damping at all
D. Radial field disintegration

Heating a magnet will ____________________?

A. Weaken it
B. Strengthen it
C. Reverse its polarity
D. Demagnetize it completely

A moving coil galvanometer of resistance 100? gives half scale deflection for a current of 20mA. What will be the potential difference across it ?

A. 4 volt
B. 5 volt
C. 2 volt
D. 0.4 volt