of the ye was closed-loop the undamped DINES SAM 48 THE ACCURACY OF MEASUREMENT SYSTEMS IN THE STEADY STATE Table Prob. 2. 3.2 Element Pressure sensor Deflection bridge Amplifier Recorder Linear sensitivity K 10QP 4x10 10 mV m 250 PamV Error bandwidth 20.005 2 25 x 10 mV 20.5 mV ±100 Pa A pressure measurement system consists of a pressure sensor, deflection bridge, amplifier and the system (a) (b) element in Table Pm Calculate the standard deviation d, of the error distribution function Given that the recorder is incorrectly adjusted so that its sensitivity is 225 Pa m calculate the mean eror & for an input pressure of 5 x 10' Pa 3.3 Figure Prob. 3 shows a block diagram of a force transducer using negative feedback. The elastic sensor gives a displacement output for a force input, the displacement sensor gives a voltage output for a displacement input. V, is the supply voltage for the displacement sensor. (a) Calculate the output voltage F, when V-10 V, F-50 N V-1.5 V, F-50 N. Comment on the practical significance of the variation of the supply voltage V, (i) (ii) (b) Figure Prob. 3. Input force Output voltage Balancing force 10+ Elastic force sensor 100x V Displacement sensor 10³ Amplifier 10 Coil and magnet 3.4 Figure Prob. 4 is a block diagram of a voltmeter. The motor pr to voltage V, and the output angular displacement 8 of the stiffness K, of the spring can vary by ±10% about the nom Given that the following are available: (a) (i) a d.c. voltage amplifier of gain 1000 (ii) a voltage subtraction unit (iii) a stable angular displacement transducer of sensitiv draw a block diagram of a modified system using these on effect of changes in K, (b) calculate the effect of a 10% increase in V inure Prob. 4. K-2x 10-1 T Table