The equivalent circuit of the capacitor shown below is
Due to initial condition, at t = 0 capacitor will act as a constant voltage source (at t = 0, capacitor acts as short-circuit). Hence, option (d) is correct.
The strength of current in 1 Henry inductor changes at a rate of 1 A/sec. The magnitude of energy stored in the inductor after 3 sec is
∴ Current in the inductor after 3 sec is
1= 3 A
Hence, energy stored after 3 sec.
The current and voltage profile of an element vs time has been shown in given figure. The element and its value are respectively
⇒ Since V is not proportional to R therefore, the element can’t be a resistor.
⇒ At t = 5 ms, even if i ≠ 0, the element behaves as a short circuit therefore, the element can’t be a capacitor (since at t = 0 only capacitor behaves as short circuit).
⇒The current at t = 0 is zero and at t = 5 ms voltage across the element is zero therefore, the element must be an inductor (at t = 0, an inductor acts as open circuit and at t =∞ it behaves as short circuit).
From the given voltage and current profile, we have
The equivalent circuit of the inductor shown below is
Figure shown below exhibits the voltage-time profile of a source to charge a capacitor of 50 μF. The value of charging current in amperes is
From given figure,
The equivalent capacitance across the given terminals A-B is
The equivalent combination of C2 and C3.
The equivalent combination of this 1 μF and
C1 = 2μF is
C1+ 1 μF = 3μF
Hence, the equivalent capacitance between terminals A and B is
The charging time required to charge the equivalent capacitance between the given terminals a-b by a steady direct current of constant magnitude of 10 A is given by
Equivalent capacitance between terminals a-b is
An ac voltage of 220 V is applied to a pure inductance of 50 H. If the current is 5 A, the instantaneous value of voltage and current will be respectively given by
Max. value of current,
Assuming voltage as the reference phasor,
The voltage and current through a circuit element is v= 100 sin (314 t + 45°) volts and i = 10 sin (314 t - 45 ° ) amps.
The type of circuit element and its value will be respectively
The phase difference between v and i is
Since v leads i therefore, the circuit element is an inductor.
The equivalent inductance for the inductive circuit shown below at terminal “ 1 - 2 ” is
Converting the internal star connected inductance to an equivalent delta, the circuit reduces as shown below.
Hence, equivalent circuit becomes as shown below.