Q.1
An induced voltage is produced as a result of a dc voltage.
Q.2
Inductance is the property of an inductor that produces an opposition to any change in current.
Q.3
An inductor and a resistor are in series with a sine wave voltage source. The frequency is set so that the inductive reactance is equal to the resistance. If the frequency is increased, then
Q.4
A 320 µH coil is in series with a 3.3 kΩ resistor. How long does it take for current to build up to its full value?
Q.5
A 240 µH inductor is equivalent to a
Q.6
An ohmmeter is connected across an inductor and the pointer indicates zero ohms. The inductor is
Q.7
The inductance of an iron-core coil decreases if
Q.8
The permeability of a core material is an indication of the ability of the material to establish a magnetic field.
Q.9
Two inductors, L1 and L2, are in parallel. L1 has a value of 25 µH and L2 a value of 50 µH. The parallel combination is in series with L3, a 20 µH coil. The entire combination is across an ac source of 60 Vrms at 300 kHz. The total rms current is
Q.10
When the current through an inductor decreases, the amount of energy stored in the electromagnetic field
Q.11
When the current through an inductor is cut in half, the amount of energy stored in the electromagnetic field
Q.12
The following coils are in parallel: 75 µH, 40 µH, 25 µH, and 15 µH. The total inductance is approximately
Q.13
Energy is stored by an inductor in an electrostatic field.
Q.14
XL is directly proportional to frequency and inductance.
Q.15
Faraday's law states that relative motion between a magnetic field and a coil induces a voltage across the coil.
Q.16
Inductance is indirectly proportional to the square of the number of turns, the permeability, and the cross-sectional area of the core.
Q.17
Inductors add in parallel.
Q.18
All coil cores are made of iron.
Q.19
The term 'choke' is more commonly used in connection with an inductor used to block off high frequencies.
Q.20
A sine wave voltage is applied across an inductor. When the frequency of the voltage is decreased, the current
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