A Wheatstone bridge may not give accurate readings if _______
1.t is not balanced
2.it is balanced
3.the voltage drop across the circuit is maximum
4.excessive current flows through the circuit
How can a Wheatstone bridge be used for the measurement of physical parameters?
1. in conjunction with a rectifier
2.along with an op amp
3. by connecting it to a thermistor
4.by making use of a transducer
How is the measurement accuracy in a bridge circuit?
1. high
2.low
3.medium
4.inaccurate
One of the simplest applications of a Wheatstone bridge is _____
1.voltage measurement
2.current measurement
3.light measurement
4.power measurement
Sensitivity is expressed in ____
1.cm/A
2.m/mA
3.mm/µA
4.inch/nA
The arms consisting of the resistances R1 and R2 are called _____
1.resistance arms
2.impedance arms
3.source arms
4. ratio arms
A galvanometer is used as a _____
1. current source
2.voltage source
3.null detector
4.input impedance
Accuracy of bridge circuit depends on _____
1.component values
2.null detector
3.voltage source
4.current source
Amount of deflection of the galvanometer depends on ______
1. resistance of the ratio arms
2.sensitivity
3.current flowing through the bridge
4. emf across the circuit
Balance condition can be obtained by _______
1. varying the standard resistance R3
2. varying the resistance arms R1 and R2
3.keeping the unknown resistance R4 constant
4.by making use of a null detector
By using the variations on a Wheatstone bridge we can _______
1.measure quantities such as voltage, current and power
2.measure high resistance values
3.measure quantities such as complex power
4.measure quantities such as capacitance, inductance and impedance
Commonly used D.C. bridges are ____
1.Schering and Anderson
2.Maxwell inductance and capacitance
3.DeSauty and Wagner
4.Wheatstone and Kelvin
Cost of maintenance of Wheatstone bridge is ______
1.low
2.high
3.depends on the components
4.depends on the source e.m.f
Effect of high dc on Wheatstone bridge.
1. no effect
2. not susceptible
3.burns the circuit
4. increases the temperature
Heating effect in the Wheatstone bridge can be avoided by ______
1.using an expensive emf source
2.limiting current to a safe value
3.using heating sinks
4.immersing the setup in ice
How is thermal emf generated?
1.when current flows
2.when voltage is applied
3.when the null detector is connected
4.when dissimilar metals come in contact
In control applications, one arm of the bridge circuit contains a _____
1.capacitive element
2.resistive element
3. inductive element
4.impedance element
Resistance R4 is known as _______
1. standard resistance
2.unknown resistance to be measured
3.resistance arm
4. input resistance
Sensitivity is defined as _____
1.amount of voltage per unit current
2.amount of power per unit voltage
3.amount of resistance per unit voltage
4. amount of deflection per unit current
Telephone companies make use of the Wheatstone bridge for ______
1.measuring the telephone resistance
2.computing the line strength
3.maintaining dialtone
4.locating the cable faults
The arm consisting of the standard known resistance R3 is known as _______
1. standard arm
2.resistance arm
3.accurate arm
4.known arm
The balance condition of a Wheatstone bridge depends on the _____
1.ratio of arms R1 and R1
2.ratio of arms R3 and R4
3.emf source and null detector
4.current source and power source
The bridge circuit can be used in _______
1. high voltage circuits
2.low power circuits
3.control circuits
4.digital integrated circuits
The main error when measuring low resistances is _____
1.power dissipation of the arms
2.voltage drop across the emf source
3.lead and contact resistance
4.current flowing through the circuit
The opposite two ends of a Wheatstone bridge consist of ____
1.voltage and current source
2.e.m.f and null detector
3.resistance and capacitance
4.inductance and impedance
The simplest type of bridge used for the measurement of medium resistances is known as ______
1.Kelvin
2.Schering
3.Anderson
4.Wheatstone
The source of error in a Wheatstone bridge is due to _____
1.range of galvanometer used
2.type of the source of emf used
3. limiting errors of the three known resistances
4. balance condition
The types of faults in a telephone line are ________
1.line to line or line to ground
2.triple line to line or line to ground
3. open circuit and short circuit
4.symmetrical and unsymmetrical
The voltage sensitivity of a galvanometer is given by ______
1.Sv = eâ„θ
2.Sv = θâ„e
3.Sv = 1â„e
4.Sv = 1â„θ
The Wheatstone bridge is used for the measurement of ______
1.1ῼ to a few megaohms
2.1kῼ to a few megaohms
3. 1Mῼ to a few gigaohms
4.1mῼ to a few ohms
Thermal compensation can be provided in a Wheatstone bridge by ____
1. using more than one resistive sensor
2.making use of a heat sink
3.using cooling fans
4. immersing the circuit into a liquid
Thermal emf can be prevented by _______
1. using more sensitive galvanometers
2.using similar metals
3.by separating the dissimilar metals
4.reducing the supply emf
Unit of voltage sensitivity is ______
1.volts per degrees
2.amps per ohms
3.degrees per volts
4.watts per amps
What are the physical parameters that are to be controlled when a bridge is used in control applications?
1.area and volume
2.mass and weight
3.pressure and temperature
4.current and voltage
What happens to the balance condition, if the source and detector are interchanged?
1. increases by a factor of 2
2.reduces to half
3. remains unchanged
4. independent of the type of source and detector
What is connected between the two ends of a Wheatstone bridge?
1.current and voltage source
2.ammeter and voltmeter
3. battery and galvanometer
4.ohmmeter and wattmeter
What is the effect of galvanometer on measurement of high resistance?
1.no effect
2.depends on the e.m.f source
3. galvanometer becomes insensitive to an imbalance
4.depends on the type of galvanometer used
What is the effect of heat on the resistances in a Wheatstone bridge?
1.no effect
2.increases the voltage drop across the circuit
3.decreases the current flowing through the circuit
4.causes a permanent change in the resistance values
What is the effect of lead wires on the Wheatstone bridge?
1.no effect
2.stabilizes the system
3.desensitizes the system
4.increases the resistance of the circuit
What is the effect of the increase in temperature on the resistance elements?
1.directly proportional
2. independent
3. inversely proportional
4.changes by a factor of 10
What is the main source of error in a null detector?
1. lower current detection ability
2.insufficient sensitivity of the null detector
3.wiring resistance
4.power dissipation
What is the relation between the sensitivity and deflection for a galvanometer?
1.directly proportional
2.inversely proportional
3.independant of each other
4.depends on the type of galvanometer used
Wheatstone bridge can’t be used for measurement of _____
1.high resistance
2.medium resistance
3.low resistance
4.accurate resistance
Wheatstone bridge consists of ______
1. 4 resistive arms
2.2 resistive arms
3.6 resistive arms
4. 8 resistive arms
Wheatstone bridge is a ________
1.a.c. bridge
2.d.c. bridge
3.high voltage bridge
4.power dissipation bridge
Wheatstone bridge is used to measure resistance in the range of _____
1. 1Ω to a few megaohms
2. 10kΩ to a few megaohms
3.100MΩ to a few gegaohms
4.100Ω to a few teraohms
Wheatstone bridge is used to measure the d.c. resistance of various types of wires for _____
1.determining their effective resistance
2.computing the power dissipation
3.quality control of wire
4.maintaining a source of constant e.m.f
Wheatstone bridge works on the principle of _____
1.full deflection
2.partial deflection
3.no deflection
4.null deflection
When current passes through the resistances in the Wheatstone bridge what happens?
1.voltage drop occurs
2.null detector burns
3.back emf is induced
4.temperature increases due to power dissipation
When the bridge is balanced, what is the current flowing through the galvanometer?
1. 0
2.depends on the ratio arms R1 and R2
3.varies by a factor of 2
4.depends on the type of null detector used