This document contains a summary of Chapter 1 of the course ET 201 Electrical Circuits. It outlines 6 practice problems related to analyzing electrical circuits: 1. Identifying parameters such as period, frequency, peak value, etc. from a given waveform. 2. Determining values of current at different times from an equation defining AC current. 3. Performing mathematical operations on complex numbers representing phasors. 4. Expressing phasor quantities in rectangular and polar form from a circuit diagram. 5. Sketching phasor diagrams and waveforms showing voltage-current relationships in resistive, capacitive and inductive circuits. 6. Calculating current and voltage values in two circuits containing resistors

1. ET 201- Electrical Circuit EOC1
END OF CHAPTER 1
1. From the given waveform explain and determine the following parameters:
a. Period
b. Frequency
c. Peak Value
d. Peak-to-Peak Value
e. RMS Value (also called effective value)
f. Average Value
(12 marks, CLO1, 1.3.2)
2. The current in an a.c circuit at any time t seconds is given by :
Determine:
a. the peak value, the periodic time, the frequency and phase angle relative to
b. the value of current when
c. the value of current when
(8 marks, CLO2, 1.3)
3. Calculate the following complex number by using mathematical operation
a. (7+j5) + (8+j6) / 25<−27º
b. (43 – j23)(89 – j4) – (40+j2)(6<8º)
c. (265 <73º)(2 <−37º)+(9<22º) / (5-j4)
(6 marks, CLO2, 2.5.1)
4. Express phasor quantity A and B in Figure 1 as rectangular form and
polar form.

2. ET 201- Electrical Circuit EOC1
Figure 1
(4 marks, CLO1, 2.3.1)
5. a. Sketch the phasor diagram and sinusoidal waveform to show the relationship between
voltage and current in purely resistive, capacitive and inductive circuit.
b. State the relationship between R, XL and XC with respect to frequency
(10 marks, CLO1, 3.1)
6. Calculate IT , IR , IL , IC ,VT , VR , VL , VC , XC and XL
a.
10 Vrms ,1 khz
1kΩ 0.1 H 1.2 μF
Figure 2
b.
1 KΩ 150 mH 0.3 μF
12 Vrms, 1.2 khz
Figure 3
(20 marks, CLO2, 3.4)

3. ET 201- Electrical Circuit EOC1