operation of whetstone bridge. 

1 Answer

Answer :

A Wheatstone bridge is widely used to measure the electrical resistance. This circuit is built with two known resistors, one unknown resistor and one variable resistor connected in the form of bridge. When the variable resistor is adjusted, then the current in the galvanometer becomes zero, the ratio of two two unknown resistors is equal to the ratio of value of unknown resistance and adjusted value of variable resistance. By using a Wheatstone Bridge the unknown electrical resistance value can easily measure.


image

Related questions

Description : tern null as it applies to bridge measurement.

Last Answer : Null measurements balance voltages so that there is no current flowing through the measuring device and, therefore, no alteration of the circuit being measured. Null measurements are generally more ... the use of standard voltmeters and ammeters, and they still have limits to their precision.

Description : operation of DSO with block diagram.

Last Answer : The input is amplified and attenuated with input amplifiers. The output of the input signal amplifiers feeds an analog to digital converter (ADC). There are numbers of ADC available. But the selection of ADC ... view the display on the CRT, the data from memory is reconstructed in analog form.

Description : operation of ramp type DVM.

Last Answer : This is given to an input comparator which will compare two signals and generates the output. One input to the input comparator is from the input and another input is from the ramp. This input voltage and ... ground and output is given. This output will stop the flow of purchase from clock

Description : operation of half wave rectifier type AC Voltmeter.

Last Answer :  Half-wave Rectifier Voltmeter The d'Arsonval meter movement only responds to the average or dc value of the current through the moving coil. In order to measure alternating ... ) input voltage signal alternating signal needs to be rectified first by using diode rectifier to produce 

Description : The operation of a ramp type Digital Voltmeter is based on the principle of (A) Voltage-to-current conversion. (B) Voltage-to-time conversion. (C) Current-to-time conversion. (D) Current-to-frequency conversion.

Last Answer : The operation of a ramp type Digital Voltmeter is based on the principle of Voltage-to-time conversion.

Description : Describe the basic SHA operation with the help of its four mode specifications.

Last Answer : Sample-and-hold amplifier (SHA) is a unity gain amplifier with a mode control switch where the input of the amplifier is connected to a time-varying signal. A trigger pulse at the mode control switch ... but other forms, such as optical and mechanical forms, are possible. Also denoted S/H.

Description : Give the operation of single phase full wave bridge controlled converter with RL load with a neat diagram. Also draw its waveform.

Last Answer : Single phase fully control bridge converter with RL load: 1. During positive half cycle of input voltage, T1 and T2 are forward biased and during negative half cycle, T3 and T4 are forward biased. Therefore, T1-T2 ... cycle till the firing of next pair of SCRs as shown in the waveform.

Description : How to Build a Bridge

Last Answer : How to Build a Bridge How to Build a Bridge Building a bridge is not an every day task, you do not see bridges going up overnight and it takes a skilled engineer to master this craft. Bridges ... this can be one of the most satisfying moments of your life to know that you have achieved your goal.

Description : How to Become a Bridge Inspector

Last Answer : How to Become a Bridge Inspector Bridge Inspectors are construction professionals who are well versed in a number of building disciplines. Among the talents of a bridge inspector are such ... secure employment in a variety of different settings, both in government agencies and private business.

Description : How to Become a Bridge Engineer

Last Answer : How to Become a Bridge Engineer Bridge Engineers are construction professionals that bear a major part of the responsibility for the safety and stability of bridges. Consequently, a bridge engineer ... new business. A well-established reputation is vital to the success of bridge engineering career.

Description : Draw circuit diagram of symmetrical configuration of bridge converter.

Last Answer : circuit diagram of symmetrical configuration of bridge converter

Description : List out advantages and disadvantages of bridge rectifier.

Last Answer : Advantages :  1. Bridge rectifier can be used in applications allowing floating output terminals i.e. not output terminal is grounded.  2. The need of center-tapped transformer is eliminated.  ... The value of the diodes used should be precise , else there will be an error in rectification

Description : Draw full bridge & half bridge configuration with common cathode.

Last Answer : Half Bridge Configuration: Full Bridge Configuration: 

Description : Wheatstone bridge

Last Answer : Wheatstone bridge

Description : A dummy strain gage is used in a quarter bridge strain gage circuit to :  (A) compensate for changes in temperature and lead wire resistance  (B) produce more output voltage from the bridge  (C) increase the sensitivity of the bridge  (D) compensate lead wire resistance only

Last Answer : A dummy strain gage is used in a quarter bridge strain gage circuit to : compensate for changes in temperature and lead wire resistance 

Description : Which of the following is true with respect to Wien Bridge? A) It does not require equal values of R or C  B) It requires that R and C values of all components must be equal C) It requires that all resistors should have equal values D) None of these

Last Answer : Which of the following is true with respect to Wien Bridge? A) It does not require equal values of R or C  B) It requires that R and C values of all components must be equal C) It requires that all resistors should have equal values D) None of these

Description : The no-load speed of a single-phase SCR bridge converter fed separately excited dc motor operating at a firing delay angle, α and flux, Φ (A) directly proportional to α and Φ (B) ... proportional to α and inversely proportional to Φ (D) directly proportional to Φ and inversely proportional to α

Last Answer : The no-load speed of a single-phase SCR bridge converter fed separately excited dc motor operating at a firing delay angle, α and flux, Φ directly proportional to α and inversely proportional to Φ

Description : A 230 V, 50 Hz phase controlled single-phase full-controlled SCR bridge converter draws 15 A constant dc current. If the source inductance is 3 mH, the drop in dc output voltage is (A) 4.5 V (B) 6.75 V (C) 9 V (D) 13.5 V

Last Answer : A 230 V, 50 Hz phase controlled single-phase full-controlled SCR bridge converter draws 15 A constant dc current. If the source inductance is 3 mH, the drop in dc output voltage is 9 V

Description : In a 230 V, 50 Hz single-phase SCR bridge converter operating at a firing delay angle, α and with large R-L load, the input source current is (A) sinusoidal current (B) constant dc current (C) continuous rectangular pulses (D) alternating rectangular pulses

Last Answer : In a 230 V, 50 Hz single-phase SCR bridge converter operating at a firing delay angle, α and with large R-L load, the input source current is alternating rectangular pulses

Description : The bridge most suited for accurate measurement of relative permittivity of dielectric materials is (A) Carey Foster Bridge (B) Anderson’s bridge (C) Heaviside Bridge modified by Campbell. (D) Schering Bridge.

Last Answer : The bridge most suited for accurate measurement of relative permittivity of dielectric materials is Schering Bridge.

Description : The bridge method commonly used for finding mutual inductance is (A) Heaviside Campbell bridge (B) Schering bridge (C) De Sauty bridge (D) Wien bridge

Last Answer : The bridge method commonly used for finding mutual inductance is Heaviside Campbell bridge

Description : The bridge most suited for measurement of a four-terminal resistance in the range of 0.001 Ohm to 0.1 Ohm (A) Wien’s bridge (B) Kelvin double bridge (C) Maxwell’s bridge (D) Shering Bridge

Last Answer : The bridge most suited for measurement of a four-terminal resistance in the range of 0.001 Ohm to 0.1 Ohm (A) Wien’s bridge (B) Kelvin double bridge (C) Maxwell’s bridge (D) Shering Bridge

Last Answer : If an inductance is connected in one arm of bridge and resistances in the remaining three arms the bridge cannot be balanced.

Last Answer : In a Schering bridge the potential of the detector above earth potential is a few volts only.

Last Answer : In an Anderson bridge, the unknown inductance is measured in terms of known capacitance and resistance.

Last Answer : For measurements on high voltage capacitors, the suitable bridge is Schering bridge.

Description : A universal RLC bridge uses?

Last Answer : A universal RLC bridge uses Maxwell Wein bridge for measurement of inductance and modified De Santy's bridge for measurement of capacitance.

Description : Explain three phase bridge inverter.

Last Answer : Three phase bridge inverter: Three phase bridge inverter converts DC voltage input to three-phase variable frequency variable voltage output. DC voltage source can be a DC source or output of the rectifier. ... in proper sequence. The switch may be thyristor or IGBT etc.

Description : Explain the operation of full bridge converters with their different operating modes. State its advantages and disadvantages.

Last Answer : Full bridge converter: Full bridge converter provides isolation between input and output. Full bridge converter is used for step up or step down the input voltage. Full bridge converter consists of four power semiconductor ... Require filter on both input and output.

Description : explain blanking times for Bridge circuit?

Last Answer : Blanking time is provided by driver circuit to power switch. Blanking time is important because the turn on input of one transistor must be delayed with turn off input of another transistor if both ... are connected in one converter leg. This blanking time helps in avoiding cross conduction.

Description : Fuel Pump Operation

Last Answer : Most people know that their cars have fuel pumps, but they don't really know how they operate. Some even pay attention to their fuel pumps only when they have already malfunctioned. It is important ... check your fuel pump for any problems because a defective pump can be dangerous while on the road.

Description : State jumping operation.

Last Answer : Jumping up operation: This process makes metal shorter and thicker and carried out at near welding temperature. Metal can be either thickened at the ends of bars or swollen in the center.

Description : With neat sketch explain four modes of operation of a TRIAC? 

Last Answer : Modes of operation of a TRIAC: There are four different operating modes of TRIAC:  1) MT2 and gate are positive with respect to terminal MT1(Mode1) : Here terminal MT2 is positive ... junction P2-N2 is forward biased, current carriers are injected and therefore, the TRIAC is turned on. 

Description : What is PLL? Explain its operation with a block diagram.

Last Answer : PLL - A phase-locked loop or phase lock loop is a control system that generates an output signal whose phase is related to the phase of an input signal Block diagram  ... to the input frequency. The phase - locked loop goes through three states free running capture and phase lock.

Description : Draw & explain operation of phase detector.

Last Answer : In phase detector, the op-Amp basically acts as a zero crossing detector. If a sine wave is applied at the i/p, we get square wave at the op-Amp o/p (at point ... to two channel of the CRO. The time duration between the pulses corresponding to voltages represent the phase between them. 

Description : State the principle of operation of d.c. motor.

Last Answer : When a current carrying conductor is placed in a magnetic field, the conductor experiences the force. The magnitude of force is given by F = BIL newton  where F – Force   B – maximum flux density   I – Current   L – Length of conductor

Description : State principle of operation of piezo-electric transducer. State its application.

Last Answer : The piezoelectric element used for converting mechanical movement into electric signals. The mechanical deformation generates charges and this charge appears as a voltage across the electrodes.  ... destructive test (NDT) equipments 6. Piezoelectric materials are used in ultrasonic transducers. 

Description : Draw and explain integrated duration curve used in system operation. 

Last Answer : Diagram of integrated duration curve used in system operation: Explanation:  Integrated duration curve is obtained from load duration curve. It is drawn in between load on Y-axis in KW/MW and the X- ... a particular time of a day can also be shown on a curve which is called as mass curve. 

Description : Explain the operation of UPS with a neat block diagram.

Last Answer : Uninterruptible-Power-Supplies (UPS): A block diagram of UPS system is shown in figure. It essentially consists of four major components: i)Rectifier (or battery charger) ii) ... . Due to fast action requirement, transfer switch can be implemented by fast acting semiconductor devices.

Description : Describe principle of operation of Doppler type ultrasonic flow meter with diagram. 

Last Answer : Diagram: Working:  The flow meter consists of a crystal transducer mounted outside the pipe in which flow is to be measured. This transducer is a piezoelectric crystal which ... , so the frequency of the reflected wave is shifted to particle velocity, according to Doppler principle.

Description : Explain the operation of advanced gas cooled reactor.

Last Answer : Operation:- Carbon dioxide or Helium is the gas used for transferring the heat produced form the reactor core to the Heat exchanger. The gas is pumped through the reactor core at high pressure. In heat ... The AGR was designed to have a high thermal efficiency 40 %. Steam pressure is 162 Kg/cm2 

Description : Describe the operation of N channel enhancement type MOSFET with diagram.

Last Answer : As its name indicates, this MOSFET operates only in the enhancement mode and has no depletion mode. It operates with large positive gate voltage only. It does not conduct when the ... of charge carriers attracted to the positive gate. Thus drain current is controlled by the gate potential.

Description : Draw diagram of class A push-pull amplifier and explain its operation. 

Last Answer : Class A Push-pull Amplifier: The circuit diagram of class A push-pull amplifier is as shown in the fig.(a). Operation: The resistors R1 and R2 along with Vcc provide the dc biasing so as ... Vcc is applied to the collectors of transistors Q1 and Q2 through the centretapped output transformer. 

Description : Describe operation of N-channel JFET

Last Answer : Operation of N-channel JFET  1) When VGS = 0 volt: When a voltage is applied between the drain and source with a DC supply voltage VDD with VGS = 0 V, the electrons flow from source ... to zero. The gate to source voltage at which current reduces to zero is called as pinch-off voltage.

Description : What is photodiode? Draw the symbol and explain operation of photodiode. 

Last Answer : A photodiode is a light detector that converts light into an electrical current. A photodiode is a semi-conductor device, with a p-n junction and an intrinsic layer between p and n layers ... current is independent of reverse bias voltage. Reverse current is mostly depends on the light intensity.

Description : Which of the following thyristors can be used for high frequency of operation? A) TRIAC B) DIAC C) SCR D) GTO 

Last Answer : Which of the following thyristors can be used for high frequency of operation? A) TRIAC B) DIAC C) SCR D) GTO 

Description : What would happen if a power transformer designed for operation on 50 Hz (frequency) were connected to a 500 Hz (frequency) source of the same voltage:  (A) Eddy Current and Hysteresis losses will be ... Current will be too much high  (C) Transformer may start to smoke and burn  (D) No effect

Last Answer : What would happen if a power transformer designed for operation on 50 Hz (frequency) were connected to a 500 Hz (frequency) source of the same voltage:  (A) Eddy Current and Hysteresis losses will be ... will be too much high  (C) Transformer may start to smoke and burn  (D) No effect

Description : A four -quadrant operation requires two full converters connected in  (1) Series (3) Back to back (2) Parallel (4) Series Cascade

Last Answer : A four-quadrant operation requires two full converters connected in Parallel 

Description : An additional condition for parallel operation of three-phase transformers over single-phase transformers is that

Last Answer : An additional condition for parallel operation of three-phase transformers over single-phase transformers is that the transformers should belong to the same vector group

Last Answer : For the parallel operation of two or more D.C. compound generators, we should ensure that series fields of all generators should be either on positive side or negative side of the armature.