BSNL TTA ONLINE TEST - 4 Instruments and Measurements

Which one of the following meters has maximum loading effect on the circuit under measurement ?

A 150 V moving iron voltmeter of accuracy class 1.0 reads 75 V when used in a circuit under standard conditions. The maximum possible percentage error in the reading is

To measures 5 volts, if one selects a 0-100 volt range voltmeter which is accurate with in ± 1%, then the error in this measurement may be up to

Assertion (A) : It is always desirable to take the reading of an indicating instrument very close to the full scale reading.
Reason (R) : Accuracy of an indicating instrument is maximum at the full scale deflection and error increases as reading comes closer to the beginning of the scale.

If an ammeter is to be used in place of a voltmeter, we must connect with the ammeter a

In eddy current damping system, the disc employed should be of

Which of the following can act as in inverse transducer?

The total current I = I1 + I2 in a circuit is measured I1 = 150 ± 3A , I2 = 250 ± 4 A, where the limits of error are given as standard deviations. I is measured as

A first order instrument is characterized by

The ratio of change in output to the change in the input is called

The difference between the indicated value and the true value of a quantity is

Which one the following statements is correct ?
The application of the instrument in wrong manner in the procedure of measurement results in a/an

Two capacitance, C1 = 150 ± 2.4µF and C2 = 120 ± 1.5 µF are connected in parallel. What is the limiting error of the resultant capacitance C (in µF) ?

Dynamic errors are caused by

Consider the following statements :
In a measuring instrument,
1. Linearity is more important than sensitivity.
2. High precision indicates high accuracy
3. Accuracy cannot be better than resolution.
Of these statements

A resistance is measured by the voltmeter-ammeter method employing dc excitation and a voltmeter of very high resistance connected directly across the unknown resistance. If the voltmeter and ammeter reading are subject to maximum possible errors of ± 2.4 % and ± 1.0 % respectively, then the magnitude of the maximum possible percentage error in the value of resistance deduced from the measurement is nearly

Two meters X and Y require 40 mA and 50 mA, Respectively, to give full-scale Deflection, then

Assertion (A) : Precision is a necessary prerequisite of accuracy.
Reason (R) : Precision guarantees accuracy.

An ammeter of range 0-25 A has a guaranteed accuracy of 1% of full-scale reading. The current measured by the ammeter is 5 A. The limiting error in the reading is

Which of the following meter is most suitable for measuring radio frequency currents?

Schering bridge is used to measure which of the following ?

A moving coil of a meter has 100 turns, and a length and depth of 10 mm and 20 mm respectively. It is positioned in a uniform radial flux density of 200 mT. The coil carries a current of 50 mA. The torque on the coil is

Attraction and repulsion type instruments are the two different types of which instrument ?

A PMMC voltmeter is connected across a series combination of a DC voltage source V1 = 2 V and an AC voltage source V2 = 3sin4t, the voltmeters reads

An average reading digital multimeter reads 10 V when fed a triangular wave, symmetric about the axis. For the same input, an rms reading meter will read

The effect of stay megnetic fields on the actuating torque of a portable instrument is maximum when the operating field of the instrument and stay fields are

Kelvines double bridge is used to measure low resistance because

An electrodynamic meter can be used to measure

The main advantage of Anderson bridge over Maxwell bridge is that

Assertion(A): A low power factor wattmeter has special constructional features to ensure accurate measurment.
Reason(R): Extension of wattmeter range in DC circuit can be easily done by using current and potential trnasformer