Measurements Competitive Objective Questions

Competitive Exams Objective Questions from Measurements:

[1] Consider the following statements:
1. The main shortcomings of diaphragms are that they are prone to shock vibrations.
2. Diaphragms have the advantages of high accuracy and good dynamic response
3. Selection of material for diaphragms mainly depends upon temperature range and chemical nature of fluid coming in contact with diaphragm during pressure measurement.
Which of the above statements is/are correct? [IES2010]
A. 1,2 and3
B. 2 and 3 only
C. 1 only
D. 1 and 2 only

[2] If reflection coefficient for voltage be 0.6, the voltage standing wave ratio(VSWR) is [IES2010]
A.0.66
B.4
C.1.5
D.2

[3] A resistance strain gage with gage factor (S_f) of 2 is bonded to a steel member,which is subjected to a strain of 1 x 10^-6.The original resistance value of this strain gage is 120Ω.The change in resistance due to the applied strain is [IES2010]

A. 60Ω
B. 240 x 10^-6Ω
C. 240Ω
D. 60 x 10^-6Ω

[4] Consider the following statements: [IES2010]

Piezoelectric materials
1. Crystal can be shown as electrical equivalent circuit similar to an inductor and a capacitor(Tank circuit).
2. Quartz,Rochelle salt,tourmaline.
3. Used in voltage stabilizers.
4. This exhibits the reverse effect of electrostriction.
Which of the above statements are correct?
A. 1,2 and 4 only
B. 1 and 2 only
C. 2 and 4 only
D. 1,2,3 and 4

[5] Consider the following units for the measurement of pressure directly: [IES2010]

1. Rolta meter
2. Bourdon tube
3. Planti meter
4. Vanes
Of these, the pressure can be measured by
A. 1 and 2 only
B. 3 and 4 only
C. 2 only
D. 1,2,3 and 4

[6] The measurement of Hall coefficient of a semiconductor with one type of charge carrier gives the information about [IES2010]

A. Sign of charge carrier
B. Density of charge carrier
C. Both sign and density of charge carrier
D. Mass of the charge carrier

[7] A piezoelectric crystal has a thickness of 2.5mm and a voltage sensitivity of 0.05Vm/N. The piezoelectric crystal is subjected to an external pressure of 1.6 x 10⁶N/m²,then the corresponding output voltage is, [IES2010]

A. 200V
B. 3.2 x 10⁹V/m of thickness
C. 0.07 x 10^-9V/(m³/New)
D. 200m V

[8]The two inputs of a CRO are fed with two stationary periodic signals. In the X-Y mode, the screen shows a figure which changes from ellipse to circle and back to ellipse with its major axis changing orientation slowly and repeatedly. The following inference can be made from this. [GATE2009]

A. The signals are not sinusoidal

B. The amplitudes of the signals are very close but not equal

C. The signals are sinusoidal with their frequencies very close but not equal

D. There is a constant but small phase difference between the signals

[9]The pressure coil of a dynamo meter type wattmeter is [GATE2009]

A. Highly inductive

B. Highly resistive

C. Purely resistive

D. Purely inductive

[10]The measurement system shown in the figure uses three sub systems in cascade whose gains are specified as G1, G2 and 1/G3. The relative small errors associated with each respective subsystem G1, G2,G3 are ε₁,ε₂ and ε₃.The error associated with the output is [GATE2009]