MCQ
4321. No eddy current and hysteresis losses occur in-
Electrostatic instruments
PMMC instruments
Moving iron instruments
Electrodynamo meter instruments
4322. Most sensitive galvanometer is-
Elastic galvanometer
Vibration galvanometer
Duddlb galvanometer
Spot ballistic galvanometer
4323. The two pressure coils of a single phase power factor meter have---
The same dimensions and the same number of turns
The same dimension but different number of turns
The same number of turns but different dimensions
None of the above
4324. The chemical effect of current is used in---
DC ammeter hour meter
DC ammeter
DC energy meter
None of the above
4325. Resistances can be measured with the help of-
Watt-meters
Voltmeters
Ammeters
Ohmmeters and resistance bridges
4326. To measure the flux, devices used are based on-
Voltaic effect
Hall effect
Piezo-clectric effect
Photo-voltaic effect
4327. If the cross-sectional area of a magnetic field increases, but the flux remains—
the same,
the increases
decreases
none
4328. The absolute measurement of resistance is done by-
Ohm's law method
Bridge method
Rayleigh method
Lorenz method
4329. In a portable instrument, the controlling torque is provided by--
Spring
Eddy currents
Gravity
All of the above
4330. The spring material used in a spring control device should have the following property---
Should be non-magnetic
Most be of low temperature coefficient
Should have low specific resistance
All of the above
4331. The resistance can be measured most accurately by-
Voltmeter-ammeter method
Bridge method
Multimeter
Megger
4332. A moving iron ammeter may be compensated for frequency errors by-
A shunt resistance
Shunt capacitance
A series inductance
Series resistance
4333. A dynamometer wattmeter can be used for-
DC only
AC only
Both DC and AC
Any of the above
4334. An ohmmeter is a---
Moving iron instrument
Moving coil instrument
Dynamometer instrument
None of the above
4335. An instrument transformer is used to extend the range of-
Induction instrument
Electrostatic instrument
Moving coil instrument
Any of the above
4336. In a moving iron meter, the deflecting torque is proportional to--
Current through the coil
Square of the current through the coil
Sine of the measurand
Square root of the measurand
4337. A direct current can be measured by-
AD.C. potentiometer directly
A D.C. potentiometer in conjunction with a standard resistance
A D.C. potentiometer in conjunction with a volt ratio box
None of the above
4338. A megger is usually-
Moving iron type instrument
Electro-static type instrument
Hot-wire type instrument
Moving coil type instrument
4339. An ohmmeter is an instrument for measuring-
current
resistance
voltage
wattage
4340. The multiplier and the meter coil in a voltmeter are in-
Series
Parallel
Series-parallel
None of the above