Recent questions tagged principle

Description : Why have both principle and principal when they can both be used interchangeably?

Last Answer : Can they be used interchangeably? Correct me if I'm wrong, but I thought they had distinct meanings. Prinicpal being the leader of a school, or the original money down on a payment, or a sort-of ... a scientific law (and both probably having more meanings that I didn't think of). Am I mistaken?

Description : State working principle of alternator. State the meaning self and separate excitation. 

Last Answer : Working principle of alternator: When a conductor is moved in magnetic field or a magnetic field moved with respect to conductor, according to Faraday's law of electromagnetic induction, the conductor ... like battery or shaft-mounted exciter, then the excitation is said to be separate excitation.

Description : Explain the working principle of induction motor. 

Last Answer : Working principle of induction motor: * When the motor is excited with three-phase supply, three-phase stator winding carries three-phase currents & produces a rotating magnetic field of constant magnitude and ... , which tend to move the rotor in the same direction as the rotating magnetic field. 

Description : Explain with neat sketch the working principle of MIG.

Last Answer : In metal-arc inert gas welding the Weld area is shielded by an effectively inert atmosphere of argon, helium, carbon dioxide, or various other gas mixtures . The consumable bare Wire is fed automatically ... of the molten-weld puddle. Multiple-weld layers can be deposited at the joint. 

Description : Describe the working principle of Thyristor operated dimmer with the help of circuit diagram.

Last Answer : Thyristor operated dimmer: A popular thyristor operated dimmer circuit employ TRIAC-DIAC phase control for low AC power control. During each half-cycle, the capacitor charges through (R1+VR1). When the ... time constant {C (R1+VR1)}. Thus by reducing VR1 the lamp brightness can be increased.

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 :  operating principle of PUT.

Last Answer : Constructional diagram & Operating principle of PUT:  The PUT is a PNPN device similar to SCR, but its operation is similar to the UJT. The PUT behave like a UJT whose trigger voltage VP can be set ... low resistance and VAK ≈ 1V). The PUT is also referred to as a complementary SCR (CSCR). 

Description : State the working principle of gears and give its applications.

Last Answer : Working Principle:  Gears are mechanical elements which transmit motion by means of successively engaging teeth.  Gears are used to transmit motion from one shaft to another or between ... Agricultural equipment.  Industrial construction.  Mining equipment.  Automotive equipment.

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 : Describe the working principle of photoelectric pickup type tacho-generator.

Last Answer : Working: Working principle: The light passes through the holes available on the rotating disc with a specific interval, depends on the angular speed of disc having equidistant holes. The frequency of this light pulses ... by N=f/HS  N=speed  f=frequency  Hs=holes on the disc

Description : Explain construction and working principle of single phase transformer.

Last Answer : A single phase transformers is an electrical device that accepts single-phase AC power and outputs single-phase AC. PRINCIPLE... The single-phase transformer works on the principle of ... and secondary windings. Thin steel laminations shall be employed to prevent power losses from the core.

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 : State working principle of earth tester.

Last Answer : Earth tester:-The resistance of the earth is measured with the help of earth tester. It consists of a hand cranked type generator, the magnet poles, crossed coils and flexible spirals. It consists ... deflection of the pointer will indicate directly resistance in ohm of the earth under test.

Description : Draw construction of Megger and write operating principle of it.

Last Answer : Megger:  Working: Two coils the current coil and pressure coil are mounted at an angle on the same spindle and form the part of the moving system. These coils are connected to a small hand driven ... . When the instrument is not working the pointer may rest at any position on the dial.

Description : State working principle of PMMC instrument.

Last Answer : Working Principle of PMMC Instrument: When current carrying conductor is placed in a constant magnetic field, it experiences a force proportional to the current and produces proportional deflection torque. 

Description : Explain the operating principle of LASER and list applications of LASER diode.

Last Answer : A basic construction of Laser diode is as shown . A PN junction is formed by two layers of doped gallium arsenide. There is highly reflective surface at one end of PN junction and ... 6. laser scanning and light beam illumination. 7. Military applications 8. Medical surgery 9.Diamond cutting

Description : Draw symbol of LED and explain it’s working principle.

Last Answer : Construction of LED: The basic structure of LED is shown in fig.(a). The active region exists between the p and n regions. The light emerges from the active side in all the directions when electron hole-pairs ... fig.(c). In this way an LED emits light. This is the principle of operation of LED.

Description : State the working principle of transformer.

Last Answer : Working principle of transformer : Transformer works on the principle of mutual electromagnetic induction. When AC voltage is applied to the primary winding it causes ac current to flow through primary ... the secondary winding. The current flows in the secondary circuit if load is connected.

Description : The transformer works on the principle of: (A) Mutual induction (B) Mutual capacitance (C) All of the above (D) None of the above

Last Answer : The transformer works on the principle of:  Mutual induction

Description : Principle of Thermocouple is based on :  (A) Thomson effect (C) Seebeck effect (B) Peltier effect (D) Kelvin effect

Last Answer :  The  principle is  based on Seebeck   effect.

Description : D' Alembert's principle is used for?

Last Answer : D' Alembert's principle is used for reducing the problem of kinetics to equivalent statics problem.

Description : According to principle of moments?

Last Answer : According  to  principle  of  moments  clockwise  moments  equals   anticlockwise  moments.

Last Answer : A hysteresis motor works on the principle of hysteresis loss.

Description : What is the principle of DC generator?

Last Answer : principle

Description : What is the principle of DC motor?

Last Answer : principle