Maximum Power Dissipated - Analogue Electronics - Past Exam Paper, Exams of Electronics

Download Maximum Power Dissipated - Analogue Electronics - Past Exam Paper and more Exams Electronics in PDF only on Docsity! EE106 Analogue Electronics, 2008/2009 Page 1 of 7 Autumn Examinations 2008/ 2009 Exam Code(s) 1BN, 1BP, 1BEE Exam(s) 1 st Electronic Engineering 1 st Electronic & Computer Engineering 1 st Sports and Exercise Engineering Module Code(s) EE106 Module(s) Analogue Electronics Paper No. 1 Repeat Paper Yes External Examiner(s) Professor George Irwin Internal Examiner(s) Professor Gearóid ÓLaighin Mr. Gavin Corley Dr. Edward Jones Instructions: Answer all of question 1, and any 2 other questions Question 1 is compulsory and carries 40 marks Choose 2 questions from 2,3 & 4; each question carries 30 marks Duration 2 hours No. of Pages 7 (including cover page) Department(s) Electrical & Electronic Engineering Course Co-ordinator(s) Gavin Corley Requirements: MCQ Handout Statistical Tables Graph Paper Log Graph Paper Other Material Standard Mathematical Tables EE106 Analogue Electronics, 2008/2009 Page 2 of 7 Question 1 is compulsory 1. (a) For the circuit shown in Figure 1.1 calculate: (i)The total resistance of the circuit, RT [4 marks] (ii)The total current IT, flowing in the circuit [1 marks] Figure 1.1 1. (b) For the circuit shown in Figure 1.2 calculate: (i) The value of the load resistor (RLoad) which will ensure maximum power transfer to the load. [3marks] (ii) The maximum power dissipated in RLoad [2 marks] Figure 1.2 1. (c) From the sawtooth waveform shown in Figure 1.3 calculate: (i) The period (T) of the waveform. [1 marks] (ii) The frequency (f) of the waveform. [1 marks] (iii) The DC offset of the waveform. [1 marks] (iv) The amplitude of the waveform. [1 marks] (v) The peak to peak value (Vp-p) of the waveform [1 marks] Figure 1.3 EE106 Analogue Electronics, 2008/2009 Page 5 of 7 2. For the circuit of Figure 2: (a) Calculate the current flowing in the 60Ω resistor due to the 50V voltage source. [7 marks] (b) Calculate the current flowing in the 60Ω resistor due to the 20V voltage source. [7 marks] (c) Calculate the current flowing in the 60Ω resistor due to the 3A current source. [7 marks] (d) Using the principle of superposition, calculate the total current and power dissipated in the 60Ω resistor. [9 marks] Figure 2 EE106 Analogue Electronics, 2008/2009 Page 6 of 7 3. (a) For the circuit of Figure 3: (i) Determine the Thévenin equivalent of the circuit inside the box (without the load circuit attached). [12 marks] (ii) Proceed to draw the Norton equivalent of the same circuit [4 marks] (iii) Derive an expression for the total resistance of the load circuit shown on the right of figure 3.1. Proceed to determine what value of R will lead to the maximum power being delivered to the load circuit. [4 marks] Figure 3 (b) Derive an expression for the RMS value of a sinusoidal waveform Vpsin(ωt) in terms of it’s peak value Vp. [10 marks] EE106 Analogue Electronics, 2008/2009 Page 7 of 7 4. (a) Figure 4 shows a series connected RLC circuit. (i) Determine the total impedance (Z) of the circuit. [5 marks] (ii) Find the value of the capacitor in Farads and the inductor in Henries. [5 marks] (iii) Calculate the magnitude of the supply current I, and voltages VR, VL,VC. [5 marks] (iv) What is the average power delivered to the circuit? [5 marks] Figure 4 (b) A smoothing capacitor is to be added to a half wave rectifier circuit with input: v(t) = 10sin(120πt) and load resistance RL = 3kΩ. (i) Calculate the value of the capacitance necessary in order to keep the ripple of the output voltage below 10%. [6 marks] (ii) Plot two cycles of the smoothed output voltage waveform. Specify an approximation to the average output voltage when the smoothing capacitor is attached. [4 marks]