Why in electric motor or generator heating due to current involves dissipation of electrical energy?

Why in electric motor or generator heating due to current involves dissipation of electrical energy?
by

1 Answer

Answer :

In electric motor or generator heating due to current involves dissipation of electrical energy because as the current increases there will be I2R losses. More current flow means more the heat will be generated and as the temperature of conductor increase its resistance increases.

by

Related questions

Unnecessary and frequent applications of varnish to the generator windings to repair defective insulation will result in ____________. A. heavy coatings of varnish interfering with heat dissipation B. deficient air gap clearance and eventual damage to the casing C. failure of the rectifier assembly D. a built-up of varnish without changing generator operation

Description : Unnecessary and frequent applications of varnish to the generator windings to repair defective insulation will result in ____________. A. heavy coatings of varnish interfering with heat dissipation B. ... of the rectifier assembly D. a built-up of varnish without changing generator operation

Last Answer : Answer: A

Choose the best definition of dielectric loss. a) Absorption of electric energy by dielectric in an AC field b) Dissipation of electric energy by dielectric in a static field c) Dissipation of heat by dielectric d) Product of loss tangent and relative permittivity

Description : Choose the best definition of dielectric loss. a) Absorption of electric energy by dielectric in an AC field b) Dissipation of electric energy by dielectric in a static field c) Dissipation of heat by dielectric d) Product of loss tangent and relative permittivity

Last Answer : a) Absorption of electric energy by dielectric in an AC field

Will there be infinite energy when we connect electric motor and electric generator to a cycle?

Description : Will there be infinite energy when we connect electric motor and electric generator to a cycle?

Last Answer : No, because they both don't have 100% efficiency practically, so there will be losses.

The heated parts of an electrical machine dissipate heat into their surroundings by which of the following modes of heat dissipation ? (a) Conduction (b) Convection (c) Radiation (d) All ofthe above

Description : The heated parts of an electrical machine dissipate heat into their surroundings by which of the following modes of heat dissipation ? (a) Conduction (b) Convection (c) Radiation (d) All ofthe above

Last Answer : (d) All ofthe above

The effects due to electric current are: I. Magnetic effect II. Heating effect III. Luminous effect

Description : The effects due to electric current are: I. Magnetic effect II. Heating effect III. Luminous effect Application working on which effect can be used on AC as well as DC supply? a. I only b. II only c. II and III only d. I, II only

Last Answer : The effects due to electric current are: I. Magnetic effect II. Heating effect III. Luminous effect Application working on which effect can be used on AC as well as DC supply? a. I only b. II only c. II and III only d. I, II only

Due to energy dissipation by viscous forces in air, if simple harmonic variations of a pendulum die away after some time, then oscillation is said to be: A. undamped B. free C. damped D. dependent

Description : Due to energy dissipation by viscous forces in air, if simple harmonic variations of a pendulum die away after some time, then oscillation is said to be: A. undamped B. free C. damped D. dependent

Last Answer : damped

A device which converts chemical energy into electrical energy is called -----? A. motor B. generator C. moving-coil meter D. battery (Answer)

Description : A device which converts chemical energy into electrical energy is called -----? A. motor B. generator C. moving-coil meter D. battery (Answer)

Last Answer : D. battery (Answer)

A device that converts mechanical energy into electric energy is called----? A. Motor. B. Transformer. C. Coil. D. Generator?

Description : A device that converts mechanical energy into electric energy is called----? A. Motor. B. Transformer. C. Coil. D. Generator?

Last Answer : B. Transformer.

Which of the following converts electric energy into mechanical energy: a. Transformer b. DC generator c. Motor d. AC generator

Description : Which of the following converts electric energy into mechanical energy: a. Transformer b. DC generator c. Motor d. AC generator

Last Answer : d. AC generato

A fuse will 'blow' if _____________. A. an electric motor is stopped suddenly by opening a switch B. the flow of current to the protection device is reversed C. the electrical current exceeds the rated value of the fuse D. unequal resistors are connected in parallel

Description : A fuse will 'blow' if _____________. A. an electric motor is stopped suddenly by opening a switch B. the flow of current to the protection device is reversed C. the electrical current exceeds the rated value of the fuse D. unequal resistors are connected in parallel

Last Answer : Answer: C

An electrical connection between the wiring of an electric motor and its metal frame is known as a/an _____________. A. eddy current B. ground C. impedance D. flux leakage

Description : An electrical connection between the wiring of an electric motor and its metal frame is known as a/an _____________. A. eddy current B. ground C. impedance D. flux leakage

Last Answer : Answer: B

The mcrease in heat dissipation by air blasts is due to increase in (a) conduction (b) convection (e) radiation (d) any ofthe above

Description : The mcrease in heat dissipation by air blasts is due to increase in (a) conduction (b) convection (e) radiation (d) any ofthe above

Last Answer : (b) convection

Alternating current generator converts.......... energy into electrical energy? a. mechanical energy b. chemical energy c. solar energy d. potential energy

Description : Alternating current generator converts.......... energy into electrical energy? a. mechanical energy b. chemical energy c. solar energy d. potential energy

Last Answer : a. mechanical energy

Which of the listed electrical devices is represented by the symbol shown in the illustration? EL-0055 A. Fixed resistance resistor B. Coil with magnetic core C. DC motor or generator shunt field D. Transformer

Description : Which of the listed electrical devices is represented by the symbol shown in the illustration? EL-0055 A. Fixed resistance resistor B. Coil with magnetic core C. DC motor or generator shunt field D. Transformer

Last Answer : Answer: D

When the conduction current density and displacement current density are same, the dissipation factor will be a) Zero b) Minimum c) Maximum d) Unity

Description : When the conduction current density and displacement current density are same, the dissipation factor will be a) Zero b) Minimum c) Maximum d) Unity

Last Answer : d) Unity

The device used for converting mechanical energy into electrical energy is called a/an (a) cell (b) transformer (c) dynamo (d) electric motor

Description : The device used for converting mechanical energy into electrical energy is called a/an (a) cell (b) transformer (c) dynamo (d) electric motor

Last Answer : Ans:(c)

Which of the following devices converts electrical energy into mechanical energy? (a) Dynamo (b) Transformer (c) Electric motor (d) Inductor

Description : Which of the following devices converts electrical energy into mechanical energy? (a) Dynamo (b) Transformer (c) Electric motor (d) Inductor

Last Answer : Ans:(c)

The electric motor converts - (1) Electrical energy into mechanical energy (2) Mechanical energy into electrical energy (3) Electrical energy into light energy (4) None of these

Description : The electric motor converts - (1) Electrical energy into mechanical energy (2) Mechanical energy into electrical energy (3) Electrical energy into light energy (4) None of these

Last Answer : (1) Electrical energy into mechanical energy Explanation: A generator converts mechanical energy into electrical energy, while a motor does the opposite - it converts electrical energy into mechanical energy.

In an electric motor, the energy transformation is from _______. (1) electrical to chemical (2) chemical to light (3) mechanical to electrical (4) electrical to mechanical

Description : In an electric motor, the energy transformation is from _______. (1) electrical to chemical (2) chemical to light (3) mechanical to electrical (4) electrical to mechanical

Last Answer : (4) electrical to mechanical Explanation: An electric motor is an electrical machine that converts electrical energy into mechanical energy. The reverse of this would be the conversion of mechanical energy into electrical energy and is done by an electric generator.

Which of these is the purpose of the power-split device? • To split electrical energy into mechanical energy • To allow both the engine and electric motor to propel the vehicle • To recharge the battery while braking

Description : Which of these is the purpose of the power-split device? • To split electrical energy into mechanical energy • To allow both the engine and electric motor to propel the vehicle • To recharge the battery while braking

Last Answer : • To allow both the engine and electric motor to propel the vehicle

Which of these is the purpose of power-split device a) To split Electrical Energy into Mechanical Energy. b) To allow both the engine and Electric motor to propel the vehicle c) To recharge the battery while braking d) To recharge the brakes while driving

Description : Which of these is the purpose of power-split device a) To split Electrical Energy into Mechanical Energy. b) To allow both the engine and Electric motor to propel the vehicle c) To recharge the battery while braking d) To recharge the brakes while driving

Last Answer : b) To allow both the engine and Electric motor to propel the vehicle

Briefly explain how an electrical generator converts mechanical energy into electrical energy

Description : Briefly explain how an electrical generator converts mechanical energy into electrical energy.

Last Answer : Working principle of DC generator: * Working principle of DC generator is the principle of dynamically induced emf or electromagnetic induction. * According to this principle, when flux is cut by a conductor, an ... , the flux is cut by the armature winding and an emf is dynamically induced in it. 

Regarding an AC generator connected to the main electrical bus; as the electric load and power factor vary, a corresponding change is reflected in the generator armature reaction. These changes in armature reaction are compensated for by the __________ A. governor speed droop setting B. voltage regulator C. balance coil D. phase-balance relay

Description : Regarding an AC generator connected to the main electrical bus; as the electric load and power factor vary, a corresponding change is reflected in the generator armature reaction. These changes in ... . governor speed droop setting B. voltage regulator C. balance coil D. phase-balance relay

Last Answer : Answer: B

Which of the following quantity maintains the same direction whether a D.C. machine runs as a generator or as a motor a. Induced e.m.f. b. Armature Current c. Field Current d. Supply Current

Description : Which of the following quantity maintains the same direction whether a D.C. machine runs as a generator or as a motor a. Induced e.m.f. b. Armature Current c. Field Current d. Supply Current  

Last Answer : Which of the following quantity maintains the same direction whether a D.C. machine runs as a generator or as a motor a. Induced e.m.f. b. Armature Current c. Field Current d. Supply Current  

Hysteresis in a direct current generator is indicated by _____________. A. arcing at the brushes B. pulsating terminal current C. heating of the armature core D. hunting and over control

Description : Hysteresis in a direct current generator is indicated by _____________. A. arcing at the brushes B. pulsating terminal current C. heating of the armature core D. hunting and over control

Last Answer : Answer: C

What is the advantage of sidetone? A. High transmission efficiency B. Results to a strengthened signal C. No energy dissipation D. Assures that the telephone is working

Description : What is the advantage of sidetone? A. High transmission efficiency B. Results to a strengthened signal C. No energy dissipation D. Assures that the telephone is working

Last Answer : D. Assures that the telephone is working

Potential flow is characterised by the (A) Irrotational and frictionless flow(B) Irrotational and frictional flow(C) One in which dissipation of mechanical energy into heat occurs(D) Formation of eddies within the stream

Description : Potential flow is characterised by the (A) Irrotational and frictionless flow (B) Irrotational and frictional flow (C) One in which dissipation of mechanical energy into heat occurs (D) Formation of eddies within the stream

Last Answer : (A) Irrotational and frictionless flow

Which of the following types of falls use parabolic glacis for energy dissipation? (A) Vertical drop fall (B) Glacis fall (C) Montague type fall (D) Inglis fall

Description : Which of the following types of falls use parabolic glacis for energy dissipation? (A) Vertical drop fall (B) Glacis fall (C) Montague type fall (D) Inglis fall

Last Answer : Answer: Option C

What is the difference between a generator and an electric motor ?

Description : What is the difference between a generator and an electric motor ?

Last Answer : The difference between generator and electric motor is given below: Mechanical power is converted into electrical power in generator , on the other hand electric power is converted into mechanical power in ... . Electric motors, on the other hand, are used almost everywhere and for many purposes.

How can an electric motor be used as a generator ?

Description : How can an electric motor be used as a generator ?

Last Answer : The basic structure of electric motor and generator is the same. Both have coils or electromagnets , permanent magnets and rotating armatures. If it is possible to rotate the armature of the electric ... can be an electric current or periodic flow. Thus electric motors can be used as generators.

The direction of propeller shaft rotation in a turbo-electric synchronous propulsion drive motor is changed by reversing the _____________. A. polarity of the propulsion motor B. polarity of the propulsion generator C. phase sequence of power to the motor D. phase sequence of power to the generator

Description : The direction of propeller shaft rotation in a turbo-electric synchronous propulsion drive motor is changed by reversing the _____________. A. polarity of the propulsion motor B. polarity of the propulsion generator C. phase sequence of power to the motor D. phase sequence of power to the generator

Last Answer : Answer: C

The propeller shaft speed in a turbo-electric, synchronous, propulsion drive motor is changed by varying the __________. A. turbine speed B. number of motor poles C. field strength of the generator D. field strength of the motor

Description : The propeller shaft speed in a turbo-electric, synchronous, propulsion drive motor is changed by varying the __________. A. turbine speed B. number of motor poles C. field strength of the generator D. field strength of the motor

Last Answer : Answer: A

In an AC synchronous motor electric propulsion plant, propeller speed is controlled by varying the _____________. A. prime mover speed B. electric coupling field strength C. number of energized main motor poles D. propulsion generator field strength

Description : In an AC synchronous motor electric propulsion plant, propeller speed is controlled by varying the _____________. A. prime mover speed B. electric coupling field strength C. number of energized main motor poles D. propulsion generator field strength

Last Answer : Answer: A

In a diesel electric plant, raising the generator's field excitation will cause the DC propulsion motor to ________. A. increase in speed B. decrease in speed C. affect generator speed only D. affect main motor speed if done in conjunction with higher generator engine speeds

Description : In a diesel electric plant, raising the generator's field excitation will cause the DC propulsion motor to ________. A. increase in speed B. decrease in speed C. affect generator speed only D. affect main motor speed if done in conjunction with higher generator engine speeds

Last Answer : Answer: A

On some diesel-electric ships, the DC propulsion motor will only attain half speed when the generator fields are fully excited. Speeds above this are obtained by _____________. A. rotating brush alignment B. raising the generator engine speed C. lowering the generator engine speed D. decreasing excitation

Description : On some diesel-electric ships, the DC propulsion motor will only attain half speed when the generator fields are fully excited. Speeds above this are obtained by _____________. A. rotating brush ... B. raising the generator engine speed C. lowering the generator engine speed D. decreasing excitation

Last Answer : Answer: B

On a vessel with turbo-electric drive, which of the following conditions would indicate that the propulsion motor had dropped out of synchronization with the propulsion generator? A. Excessive vibration of the vessel B. Tripped main motor interlocks C. Overheated crosstie busses D. Closed contact in the field circuits

Description : On a vessel with turbo-electric drive, which of the following conditions would indicate that the propulsion motor had dropped out of synchronization with the propulsion generator? A. Excessive ... Tripped main motor interlocks C. Overheated crosstie busses D. Closed contact in the field circuits

Last Answer : Answer: A

The electric motor in hybrid car can also act as_____ • A generator • A Fuel pump • Cooling fan • Compressor

Description : The electric motor in hybrid car can also act as_____ • A generator • A Fuel pump • Cooling fan • Compressor

Last Answer : • A generator

n electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a – (1) Power transmittor (2) Battery (3) Uninterrupted power supply (UPS) (4) Generator

Description : n electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a – (1) Power transmittor (2) Battery (3) Uninterrupted power supply (UPS) (4) Generator

Last Answer : (3) Uninterrupted power supply (UPS) Explanation: A Galvanic cell, also known as battery, is an electro-chemical cell that derives electrical energy from spontaneous redox reactions taking place within ... produce direct current. A battery is a set of galvanic cells that are connected in parallel.

A diesel driven emergency generator is prevented from being paralleled with the ship's service generators by __________. A. an electrical interlock system B. an automatic paralleling trip switch C. the synchronizing oscilloscope D. the reverse current relay

Description : A diesel driven emergency generator is prevented from being paralleled with the ship's service generators by __________. A. an electrical interlock system B. an automatic paralleling trip switch C. the synchronizing oscilloscope D. the reverse current relay

Last Answer : Answer: A

An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a : (1) Power transmittor (2) Battery (3) Uninterrupted power supply (UPS) (4) Generator

Description : An electrochemical cell which is used as a source of direct electrical current at constant voltage under standard conditions is called a : (1) Power transmittor (2) Battery (3) Uninterrupted power supply (UPS) (4) Generator

Last Answer : Battery

A transformer in an electric circuit serves to ____________. A. generate its own electrical power B. transform electrical energy into mechanical energy C. increase or decrease circuit voltage as required D. convert AC current to DC current

Description : A transformer in an electric circuit serves to ____________. A. generate its own electrical power B. transform electrical energy into mechanical energy C. increase or decrease circuit voltage as required D. convert AC current to DC current

Last Answer : Answer: C

The primary function of an electric motor is to ___________. A. develop torque B. generate high voltages C. produce a magnetic field D. generate high electrical resistance

Description : The primary function of an electric motor is to ___________. A. develop torque B. generate high voltages C. produce a magnetic field D. generate high electrical resistance

Last Answer : Answer: A

The processing of green tea involves brief heating of the freshly picked leaves. What could be the possible reason/s? 1. To retain green colour of leaves 2. To give it a special flavour 3. To denature leaf enzymes for preventing fermentation Which of the above reason/s is/are true? (a) Only 1 (b) 1 and 3 (c) Only 2 (d) Only 3

Description : The processing of green tea involves brief heating of the freshly picked leaves. What could be the possible reason/s? 1. To retain green colour of leaves 2. To give it a special flavour 3. To denature leaf enzymes for preventing ... reason/s is/are true? (a) Only 1 (b) 1 and 3 (c) Only 2 (d) Only 3

Last Answer : Ans:(d)

Forge welding involves heating of parts to elastic stage and joint is prepared by impact force. a) Yes b) No, it is done up to plastic stage c) Heating is done up to boiling point d) None of the listed

Description : Forge welding involves heating of parts to elastic stage and joint is prepared by impact force. a) Yes b) No, it is done up to plastic stage c) Heating is done up to boiling point d) None of the listed

Last Answer : b) No, it is done up to plastic stage

Pick out the wrong statement. (A) 'Solvates' are chemical compounds formed by solute with their solvents. When water is the solvent, then it is called a 'hydrate' (B) In heat exchanger calculations (Δt) weighted is used in place of Δt, when it involves more than one sequence of heating or cooling i.e., desuperheating & condensation or condensation & sub-cooling (C) Heat transfer co-efficient during nucleate boiling is not influenced by the agitation imparted (D) In case of short tube vertical evaporators, area of central downtake is about 50 to 100% of the total tube cross-sectional area

Description : Pick out the wrong statement. (A) 'Solvates' are chemical compounds formed by solute with their solvents. When water is the solvent, then it is called a 'hydrate' (B) In heat exchanger ... vertical evaporators, area of central downtake is about 50 to 100% of the total tube cross-sectional area

Last Answer : (C) Heat transfer co-efficient during nucleate boiling is not influenced by the agitation imparted

Carbylamine test involves heating a mixture of (a) alcoholic KOH, methyl iodide, and sodium metal (b) alcoholic KOH, methyl iodide, and primary amine (c) alcoholic KOH, chloroform, and primary amine (d) alcoholic KOH, methyl alcohol, and primary amine

Description : Carbylamine test involves heating a mixture of (a) alcoholic KOH, methyl iodide, and sodium metal (b) alcoholic KOH, methyl iodide, and primary amine (c) alcoholic KOH, chloroform, and primary amine (d) alcoholic KOH, methyl alcohol, and primary amine

Last Answer : alcoholic KOH, chloroform, and primary amine

Pick out the wrong statement.(A) Pasteurisation of milk involves moderate heating followed by cooling (B) Bakeries and breweries make use of yeasts (C) Enzyme is a complex nitrogenous compound (D) Oils and fats are alkaloids

Description : Pick out the wrong statement. (A) Pasteurisation of milk involves moderate heating followed by cooling (B) Bakeries and breweries make use of yeasts (C) Enzyme is a complex nitrogenous compound (D) Oils and fats are alkaloids

Last Answer : (D) Oils and fats are alkaloids

What is the most efficient solar electrical energy generator?

Description : What is the most efficient solar electrical energy generator?

Last Answer : Solar thermal energy technology is more efficient than photovoltaics. So when you want to heat water it's not a good idea to use electricity generated by photovoltaics. If you want to use a ... heated oil also at night. This technology has been proposed for the Desertec project in the Sahara.