০০। and i(t) is a unit step, then V(t) in the steady state is given by
ক) 4/9
খ) 4/3
গ) 0
ঘ) ∞
০১। μ0 = 8.85 x 10-12F/m.
ক) True
খ) False
০২। , i(t) =
ক) 3e-4t - e-5t
খ) 3e-4t - 2e-3t
গ) 2e-4t - 5e-2t
ঘ) 3e-4t - e-t
০৩। A 0.5 μF capacitor is connected across a 10 V battery. After a long time, the circuit current and voltage across capacitor will be
ক) 0.5 A and 0 V
খ) 0 A and 10 V
গ) 20 A and 5 V
ঘ) 0.05 A and 5 V
০৪। A 1 μF capacitor is connected to 12 V battery. The energy stored in the capacitor is
ক) 12 x 10-6 J
খ) 24 x 10-6 J
গ) 48 x 10-6 J
ঘ) 72 x 10-6 J
০৫। A 10 μF capacitor is charged from a 5 volt source through a resistance of 10 kΩ. The charging current offer 35 m sec. If the initial voltage on C is - 3 V is
ক) 0.56 mA
খ) 5.6 mA
গ) 6 mA
ঘ) 5 μA
০৬। A 10 ohm resistance and a 10 ohm capacitor are connected in series across a 100 V ac supply. The rms voltage across resistance is
ক) 1002 V
খ) 100 V
গ)
ঘ) none of the above
০৭। A 2 mH inductor with some initial current can be represented as shown below, where s is the Laplace transform variable. The value of initial current is
ক) 0.5 A
খ) 1.0 A
গ) 2.0 A
ঘ) 0.0 A
০৮। A 2-terminal network consists of one of the RLC elements. The elements is connected to an ac supply. The current through the element is 1 A. When an inductor is inserted in series between the source and the element, the current through the element becomes 2 A. What is this element?
ক) A resistor
খ) An inductor
গ) A capacitor
ঘ) Cannot be single element
০৯। A 20 Ω resistor, a 1H inductor and 1μF capacitor are connected in parallel the combination is driven by a unit step current. Under the steady state, source current flows through
ক) inductor
খ) capacitor
গ) resistor
ঘ) all
১০। A 3 phase balanced supply feeds 3 phase unbalanced load. Power supplied to the load can be measured by using
2 wattmeter
one wattmeter
3 wattmeter
Which of the above statements is correct?
ক) 1 and 2
খ) 1 and 3
গ) 2 and 3
ঘ) 3 alone
১১। A 3 phase star-connected load has one capacitor C in R phase and two equal resistances in Y and B phases.The phase sequence is RBY. Then
ক) VB0 > VY0
খ) VB0 < VY0
গ) VB0 = VY0
ঘ) VB0 = VBY
১২। A 50 Hz current has an amplitude of 10 A. The rate of change of current at t = 0.005 after i = 0 and is increasing is
ক) 2221.44 A/s
খ) 0
গ) - 2221.44 A/s
ঘ) - 3141.6 A/s
১৩। A 60 W, 23 V bulb is used for 45 minutes. The electrical energy consumed in commercial units is
ক) 2700 units
খ) 0.45 units
গ) 4.5 units
ঘ) 0.045 units
১৪। A band elimination constant k filter has series resonant circuit in series arms.
ক) True
খ) False
১৫। A battery charger can drive a current of 5A with 1Ω resistance connected at its output. If it can charge 2 V battery at 7 A rate, its Thevenin's equivalent circuit will be
ক) 7.5 in series with 0.5 Ω resistance
খ) 1.25 V in series with 1.5 Ω resistance
গ) 7.5 V in parallel with 0.5 Ω resistance
ঘ) 12.5 V in parallel with 1.5 Ω resistance
১৬। A black box has one of the elements our of R, L, C. when a 220 V a supply is connected the current supplied by source is I. when a 0.1 F capacitor is connected in parallel with the box, the current is 2I. The element is
ক) resistance
খ) inductance
গ) 0.1 F capacitance
ঘ) not identifiable on the basis of given data
১৭। A bulb rated at 60 W, 120 V is used for 30 minutes. The charge associated with this operation is
ক) 3600 C
খ) 900 C
গ) 7200 C
ঘ) 600 C
১৮। A cable has an insulation resistance of 1010 ohms. If the length is doubled, the insulation resistance will be
and i(t) is a unit step, then V(t) in the steady state is given by
, i(t) =
