Image
1.0.0
MCQ
1. Resistances can be measured with the help of-
Watt-meters
Voltmeters
Ammeters
Ohmmeters and resistance bridges
2. Wien bridge is useful for measuring-
Very high frequency
Medium frequency
Low frequency
High frequency
3. Most sensitive galvanometer is-
Elastic galvanometer
Vibration galvanometer
Duddlb galvanometer
Spot ballistic galvanometer
4. The resistance can be measured most accurately by-
Voltmeter-ammeter method
Bridge method
Multimeter
Megger
5. 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
6. 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
7. If the cross-sectional area of a magnetic field increases, but the flux remains—
the same,
the increases
decreases
none
ব্যাখ্যা: We know, B A If area is increases flux density will be decreases because they are inversely proportional to each other.
8. A megger is usually-
Moving iron type instrument
Electro-static type instrument
Hot-wire type instrument
Moving coil type instrument
9. No eddy current and hysteresis losses occur in-
Electrostatic instruments
PMMC instruments
Moving iron instruments
Electrodynamo meter instruments
10. The absolute measurement of resistance is done by-
Ohm's law method
Bridge method
Rayleigh method
Lorenz method
11. 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
12. The EMF of Weston standard cell is measured using-
Moving-iron meter
Digital Voltmeter
Moving-coil meter
Potentiometer
13. To measure the flux, devices used are based on-
Voltaic effect
Hall effect
Piezo-clectric effect
Photo-voltaic effect
14. An ohmmeter is an instrument for measuring-
current
resistance
voltage
wattage
15. The multiplier and the meter coil in a voltmeter are in-
Series
Parallel
Series-parallel
None of the above
16. The chemical effect of current is used in---
DC ammeter hour meter
DC ammeter
DC energy meter
None of the above
17. In a portable instrument, the controlling torque is provided by--
Spring
Eddy currents
Gravity
All of the above
18. একটি কোষের তড়িচ্চালক শক্তি 1.5V এবং অভ্যন্তরীণ রোধ 2Ω। এর প্রান্তদ্বয় 10Ω রোধের সাথে যুক্ত থাকলে কতটুকু তড়িৎ প্রবাহিত হবে?
0.225 A
0.125 A
40.8 A
8A
19. A moving iron ammeter may be compensated for frequency errors by-
A shunt resistance
Shunt capacitance
A series inductance
Series resistance
20. 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