Answer Happy

Q3. a) A pressure measuring system consists of a pressure transducer, a bridge circuit, amplifier and recording instrument as shown in FIGURE 23(a). The sensitivities of three of the stages are given in the table below Determine the required sensitivity of the pressure sensor, giving its units. [8 marks] Bridge 4x10°VO Amplifier 1000 Recorder 2500 Palv Amplifier Recorder Pressure Sensor Bridge Circuit FIGURE Q3(a) b) FIGURE Q3(b) shows the equivalent circuit of the amplifier used in (a) above. RS is the effective source resistance of bridge circuit and RL the effective load resistance of the recorder. Using the values of the resistances given in the table, determine the percentage error in the amplifier's output voltage if ideally Vo = GVs. [11 marks] State the ideal required values of Ri and Ro to achieve the ideal condition Vo = GVS. [6 marks) RS R R V R R 1002 R 5000 2 R 20.2 R 10002 Vs +GV FIGURE Q3(b)