In a moving coil instrument, the deflecting torque is proportional to

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In a moving coil instrument, the deflecting torque is proportional to Current.

Related questions

The deflecting torque of a moving coil instrument depends on (a) supply frequency (c) flux in the coil (b) inverse of area of coil (d) square of the voltage

In a particular meter, the deflecting torque is directly proportional to the current flowing through it, the type of meter is (a) moving coil (b) moving iron (c) induction (d) electro-static

Series resistance required to read 0-250 V with a moving coil instrument of internal resistance 2 ohm and full scale deflection of 50 mA is (a) 49998 Ω (b) 4998 Ω (c) 498 Ω (d) 49.8 Ω

A moving coil instrument has a resistance of 10 W and gives full scale deflection when carrying a current of 50 mA. To measure current upto 100 A, we will have to connect • 10 W resistance in series • 10 W resistance in parallel • 10/1999 W resistance in series • 10/1999 W resistance in parallel

The torque produced in wattmeter is proportional to

A null type of instrument as compared to a deflecting type instrument has (a) higher accuracy (b) lower sensitivity (c) faster response (d) All of the above

A moving coil instrument of resistance 5 Ohm requires a potential difference of 75 mV to give a full scale deflection. The value of shunt resistance needed to give a full scale deflection at 30 A is

The moving system of an indicating type of electrical instrument is subjected to (a) a deflecting torque (b) a controlling torque (c) a damping torque (d) All of the above

Name the material used for :- (i) Moving coil (ii) Permanent magnet in PMMC instrument.

A PMMC instrument has FSD of 100 μA and a coil resistance of 1 kΩ. To convert the instrument into an ammeter with full scale deflection of 100 mA, the required shunt resistance is (A) 1 Ω (B) 1.001 Ω (C) 0.5 Ω (D) 10 Ω

The torque, in a_______ is proportional to the square of the armature current. (A) DC shunt motor (C) 2 -phase servomotor (B) stepper motor (D) DC series motor

The effect of stray magnetic fields on the actuating torque of a portable instrument is maximum when the operating field of the instrument and the stray fields are  A) Perpendicular B) Parallel C) Inclined at 60" D) Inclined at 30°

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

The maximum torque that a synchronous motor can deliver is proportional to (1) 1/V2 (2) 1/V (3) V (4) V2

In an energymeter which coil carries the current proportional to supply voltage _____.

A permanent magnet moving coil ammeter has a coil resistance of 99 ohm and Full Scale Deflection (FSD) current of 0.1mA. Shunt resistance is 1 ohm. Current through the meter at 0.5 F.S.D is:

The main sources of Errors in Permanent Magnet moving Coil (PMMC) are due to : - a) weaking of the permanent magnet due to aging at temperature effects b) weaking of spring due to aging and temperature effects c) change of resistance of the moving coil with temperature d) all the above

An unshielded moving iron voltmeter is used to measure the voltage in an AC circuit. The stray DC magnetic field having a component along the axis will be  (1) unaffected (2) decreased (3) increased (4) either decreased or increased depending on the direction of the DC field

In a portable instrument, the controlling torque is provided by  A) Spring B) gravity C) eddy currents D) all of the above

In the case of an instrument reading of 8.3 V with a 0 to 150 voltmeter having a guaranteed accuracy of 1% full scale reading, the percentage limiting error is   (A) 1.810% (B) 0.181% (C)12.45% (D) 0.0018%

Eddy current damping cannot be used for moving iron instrument because

Two voltmeters of same range, one moving iron type and other permanent magnet moving coil type, are connected in parallel for measuring a.c. supply voltage. If the reading of MI type is 300V, the reading of PMMC type will be (a) zero (b) higher-than M.I. type (c) lower than M.I. type (d) same

Permanent magnet moving coil instruments are used for

The meter which does not have any component in it to provide control torque is (A) Electrodynamometer for current measurement (B) Electrodynamometer for voltage measurement (C) Electrodynamometer for power measurement. (D) Electrodynamometer for power factor measurement.

A moving coil meter has a resistance of 3 Ω and gives full scale deflection with 30 mA. To measure voltage up to 300 V, the external resistance to be connected in series with the instrument is (A) 9997 Ω (B) 10000 Ω (C) 997 Ω (D) 10003 Ω

The current coil of a wattmeter is connected to the C.T. of R phase. Its potential coil is connected across Y & B phases. The wattmeter measures (a) active power in R phase (b) active power of Y-phase (c) reactive power in R-phase (d) power proportional to 3-phase power if the load is balanced