Electrical & Electronics Measurements Objective Questions – Set 4

The calibration of a voltmeter can be carried out by using

A DC potentiometer is the best means available for the measurement of DC voltage because

In which of the transformer is the secondary nearly short circuited under normal operating condition?

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

Which of the quantity consists of SI unit as Candela?

A wheatstone bridge cannot be used for precision measurements because errors are introduced into on account of

Ratio of readings of two wattmeter connected to measure power in a balanced 3-phase load is 5:3 and the load is inductive. The power factor at load is

Which one of the following units is a fundamental unit?

Magnetic deflection is inversely proportional to

Standardisation of potentiometer is done in order that, they become

Which devices used to measure the temperature of an object ?

In a CRO which of following is not a part of electron gun?

The trasfer instrument which is used for standartion of a polar type AC potentiometer is

For the AC bridge circuit shown in figure at balance the value of R_d

The coil of a moving iron instrument has a resistance of 500 ohm and inductance of 1 H. It reads 250 V when a 250 V DC is applied. It series resistance is 2000 ohms its reading when fed by 250 V, 50 Hz AC will be

How many times base circuits does a dula frace CRO can have?

Which of the quantity consists of unit as Pascal ?

Which of following is not correct?

The value of L_d will be

Which amplifier in used in an electronic multimeter?

For measuring an AC voltage by an AC potentiometer it is desirable that the supply for the potenmeter is taken from

When a potentiometer is used for measurement of voltage of an unknown source, the power consume in the circuit of the unknown source under null condition is

A meter has a full-scale deflection of 90° at a current of 1 A. The response of the meter is square law. Assuming spring control, the current for a deflection at 45° will be

A thermo couple ammeter gives full scale deflection of 10 A, when it reads one fifth of the scale, the current will be

Which of following voltmeters would you use for measuring voltage across 20KΩ resistance

The use of thermocouple meters for AC measurement leads to scale which is

Figure show an RC potentiometer to measure AC voltage. It is desire that V_o/V_i should be independent of frequency. The value of C shoud be

To increase Q factor of a coil, the wire should be

A DC potentiometer is designed to measure up to about 2V with a slide wire of 800 mm. A standard cell of emf 1.18 V obtains balances at 600 mm. A test cell is seen to obtain balance at 680 mm. The emf of test cell is

The circuit in figure is used to measure the power consumed by the load. The current coil and the voltage coil of the wattmeter have 0.02 Ω and 1000 Ω resistance respectively. The measured power compared to the load power will be