# Electronic Measurement and Instrumentation January-2013

UNIT – I

1. (a) A circuit was tuned for resonance by 8 different students and the value of their resonant frequency in KH2 were recorded as 532, 548, 546, 531, 543, 536. Calculate :

(i)  Arithmetic mean

(ii)  Average deviation

(iii) Deviation from mean

(iv) Variance.

(b) Write short notes on :

(i) Systematic error

(h) Random error

(iii) Normal error

(iv) Gross error.

OR

1. (a) Write short notes on :

(i)  Accuracy

(ii) Repeatability

(ii)  Standard deviation

(iii) Precision.

(b) Explain Gaussian erron analysis indetail, also write down all the properties of normal distribution.

(c)  Define the role of non-linearity and hysterisis on error.

UNIT – II

2.  (a) Explain the working of successive approximation type digital voltmeter with suitable diagram.

(b) Explain the construction and working principle of vector impedance Q meter with neat sketch.

OR

(a) Define and compare the ramp type voltmeter and integrating type voltmeter with respect to working principle, advantages and disadvantages.

(b) Find the equivalent parallel resistance and capacitance that causes wein bridge to null with the R\ -3.1 kQ, (\ = 5.2 \\f. R2 ~ 25 kQ, 4 = 100 kQ and / = 2.5 kHz component values.

UNIT – III

3. (a) Explain following in details :

(a) Multibeam and multirace oscilloscope.

(b) Dual storage CRO.

(b) The deflection sensitivity of an CRO is 35 V/cm. If the distance from the deflecting plate to the CRT screen is 16 cm. The length of the deflecting plate is 2.5 cm and the distance between the deflecting plate is 1.2 cm. What is the accelerating voltage ?

OR

3 (a) Write down the working principle with required block diagram of s amp lin g oscilloscop e.

UNIT – IV

4. (a) Explain the working frequency selective analyser with suitable diagram and its applications, also differentiate it with respect to heterodyne wave analyser in detail,

OR

(a) Explain random noise generator.

(b)) Why are signal generation needed ? Define sweep frequency generator.

UNIT – V

5. (a)  Explain the construction details and working principle of LVDT. How displacement is measured by LVDT ?

(b) Enumerate the transducer principle for measurement of following :

(a) Angular velocity

(b) Humidity

(c) Gas flow

(d) Temperature.

OR

(a) What is differential arrangement for taking output from the inductive transducer. Give advantages of their arrangement.

(b)) What are thermistor ? Explain their different form of construction. Give the characteristics curve with applications of thermistor.