Q. In an induction wattmeter, the shading bands are made of non conducting material.

View solution

Q. Consider the following statements

1. Thermistor is more sensitive than platinum resistance thermometer
2. The resistance of thermistor is solely a function of its absolute temperature whether the source of heat is external or internal
3. Thermistor has linear temperature-resistance relationship
4. Thermistor has linear negative temperature coefficient

Of the Statements, the correct statements are

View solution

Q. A moving coil meter has 10 Ω resistance and requires 40 mA for full scale deflection. The shunt resistance required to convert it into 0-2 A ammeter is

View solution

Q. Which of the following instruments can be used for dc as well ac upto a few MHz?

1. Moving iron instrument
2. Thermocouple instrument
3. Induction instrument
4. Moving coil instrument

Select the correct answer as per following codes

View solution

Q. Assertion (A): Strain measurement using strain gauge invariably requires a dummy strain gauge.

Reason (R): The resistance of strain gauge depends on temperature.

View solution

Q. If a shunt of 200 Ω resistance is used with a galvanometer of 1000 Ω resistance, the multiplying power is

View solution

Q. Insertion of a dielectric material between the plates of an air capacitor

View solution

Q. Two ammeters A and B are connected in parallel in a circuit carrying 100 A. Their resistances are 0.8 mΩ. Their readings will be.

View solution

Q. In household energy meters the flux of series magnet is in phase with current but the flux of shunt magnet lags the voltage by 88°. The reading of energy meters

View solution

Q. Assertion (A): A universal RLC bridge has a battery and also a high frequency ac source.

Reason (R): RLC bridge uses a Wienbridge arrangement for measuring capacitance.

View solution

Q. A capacitance transducer can be used to measure

View solution

Q. The dynamometer principle can be used for

View solution

Q. Assertion (A): In hot wire instrument the material of hot wire in generally platinum iridium.

Reason (R): A hot wire ammeter is suitable for ac only

View solution

Q. The scale of hot wire ammeter is

View solution

Q. A moving coil meter has a shunt of 0.02 Ω resistance. If coil resistance is 1000 Ω and a potential difference of 500 mV is required across it to cause full scale deflection, the current through shunt is

View solution

Q. The emf of a Weston cell is 1.286 V.

View solution

Q. The power factor of a single phase load can be calculated if instruments available are

View solution

Q. A variable reluctance type tachometer has 150 teeth on rotor. The counter records 13500 pulse/sec. The rotational speed is

View solution

Q. The current through the coil of an electromagnet is doubled. The magnetic field around the coil

View solution

Q. In a moving iron voltmeter the coil has a resistance of 20 Ω and an inductance of 0.3 H. The swamping resistance in 2000 Ω. To ensure correct reading with dc as well as 50 Hz ac, the value of capacitor to be connected in parallel with swamping resistance should be

View solution