Download Assignment-2 File - Shankersinh Vaghela Bapu Institute of Technology

SHANKERSINH VAGHELA BAPU INSTITUTE OF TECHNOLOGY, VASAN
ELEMENTS OF ELECTRICAL ENGINEERING
ASSIGNMENT: 2
SINGLE PHASE AC CIRCUIT
1) Explain with the aid of a phasor diagram the phenomenon of resonance in a circuit
containing an inductor, a capacitor and a resistor in series.
2) Distinguish between (i) apparent power (ii) active power and (iii) reactive power
3) Prove that average power consumption in pure inductor is zero when a.c. voltage is
applied
4) Give the comparison of series resonance and parallel resonance
5) Explain magnetic hysteresis
6) Prove that current through pure inductor is always lagging by 90o to its voltage and
power consumed is zero
7) Three impedances Z1 = 5-j10 Ω, Z2 =2+j20 Ω and Z3 = 4+j2 Ω are connected in
parallel. If the total current is 20A, find the current shared by each.
8) Compare series and parallel resonance.
9) Discuss resonance in R-L-C series circuit. Explain how pf, XL and R vary with
frequency.
10) Define power factor. What is the power factor of a pure inductor? Give the difference
between active and reactive power.
11) Explain Magnetic Hysteresis phenomena using hysteresis loop.
12) Explain the phenomena of generation of Alternating voltages and currents and derive
expression for it with suitable diagrams
13) Define the following terms with respect to AC waveforms (1) Form factor (2)
Frequency
14) Define the following terms with respect to AC waveforms (1) phase (2) Time Period
15) Define (i) form factor (ii) peak factor. Obtain the rms value and average value of half
wave rectified sinusoidal voltage wave.
16) Define following terms in connection with A.C wave forms : (i) Frequency (ii) phase
& phase difference (iii) Time Period (iv) form factor (v) R. M. S. Value (vi) Average
Value
17) Define the term (1) reactance, (2) inductive reactance and (3) capacitive reactance and
explain how it depends on frequency in an A. C. circuit
18) A series RLC circuit consists of a resistance of 500 5, inductance of 50mH and a
capacitance of 20 pF. Find 1.) The resonant frequency. 2.) The Q-factor of the circuit
at resonance. 3 ) The half power frequency
19) Discuss different methods of representation of vector quantities.
20) Derive the equation of power in a single phase AC circuit in vector form only
SHANKERSINH VAGHELA BAPU INSTITUTE OF TECHNOLOGY, VASAN
ELEMENTS OF ELECTRICAL ENGINEERING
21) Prove that the average power consumption in a pure inductive or capacitive circuit is
zero.
22) Prove that in a purely capacitive circuit power consumed is zero when a.c. voltage is
applied. Draw relevant phasor diagram and waveforms
23) An inductive coil of resistance R and inductance L is connected in parallel with a
capacitor of C. Derive an expression for resonant frequency and Q factor
24) A resistor of 40 Ω and an inductor of 0.2 H and capacitor of 120 μF are connected in
parallel across 230V, 50 Hz supply. Find:(i) the current of each branch (ii) the
resultant current (iii) power factor of the circuit