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10+ DocMode Health Technologies Interview Questions and Answers
Q1. What is diode types of diode
Diodes are electronic components that allow current to flow in one direction only. Common types include PN junction diodes, Zener diodes, Schottky diodes, and light-emitting diodes (LEDs).
PN junction diodes: Basic diodes that allow current to flow in one direction only.
Zener diodes: Diodes that operate in the reverse breakdown region and are used for voltage regulation.
Schottky diodes: Diodes with a lower forward voltage drop compared to PN junction diodes.
Light-emitting diod...read more
Q2. Difference between AC and DC motor
AC motors use alternating current and are more commonly used for industrial applications, while DC motors use direct current and are often used in household appliances.
AC motors use alternating current, while DC motors use direct current
AC motors are more commonly used in industrial applications, while DC motors are often used in household appliances
AC motors are generally more efficient and require less maintenance compared to DC motors
AC motors are easier to control speed a...read more
Q3. Types of motor and working principles
Types of motors include DC motors, AC motors, synchronous motors, and induction motors. Each type operates based on different principles.
DC motors operate using direct current and have a commutator to switch the current direction, examples include brushed and brushless DC motors.
AC motors operate using alternating current and include types like synchronous motors and induction motors.
Synchronous motors rotate at a constant speed determined by the frequency of the AC power sup...read more
Q4. Types of motor and working principle
Types of motors include DC motors, AC motors (induction, synchronous), stepper motors, and servo motors. Each type operates based on different principles.
DC motors operate on the principle of Lorentz force, where a current-carrying conductor experiences a force in a magnetic field.
AC induction motors work on the principle of electromagnetic induction, where a rotating magnetic field induces current in the rotor.
AC synchronous motors operate by synchronizing the speed of the r...read more
Q5. What is blast furnace
A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally iron.
Used for smelting iron ores to produce iron
Consists of a furnace chamber with a stack and tuyeres
Operates at high temperatures using coke as fuel
Produces molten iron and slag as byproducts
Q6. What is electromagnetic field
An electromagnetic field is a physical field produced by electrically charged objects. It affects the behavior of charged objects in the vicinity of the field.
Consists of electric and magnetic components
Generated by electric charges and currents
Can be static or dynamic
Used in various applications such as wireless communication and MRI machines
Q7. What is cooking and crawling
Cooking and crawling are terms used in electrical engineering to describe the movement of a circuit breaker's contacts.
Cooking refers to the slow separation of the contacts when the circuit breaker is opened under load.
Crawling refers to the movement of the contacts due to the presence of small currents even when the circuit breaker is in the closed position.
Q8. Working principle of Transformers
Transformers work on the principle of electromagnetic induction to transfer electrical energy between two or more circuits.
Transformers have two coils of wire, known as primary and secondary coils, which are wound around a core made of ferromagnetic material.
When an alternating current flows through the primary coil, it creates a changing magnetic field around the coil.
This changing magnetic field induces a voltage in the secondary coil through electromagnetic induction, resu...read more
Q9. What is V F D
VFD stands for Variable Frequency Drive, a type of motor controller that drives an electric motor by varying the frequency and voltage supplied to the motor.
VFDs are used to control the speed and torque of AC motors in various applications.
They are commonly used in HVAC systems, industrial pumps, fans, and conveyor systems.
VFDs can improve energy efficiency by matching the motor speed to the actual load requirements.
They can also provide soft starting and stopping of motors, ...read more
Q10. What is turbine
A turbine is a machine that converts the energy from a fluid flow into mechanical energy.
Turbines are commonly used in power plants to generate electricity from steam or water flow.
There are different types of turbines such as steam turbines, gas turbines, and water turbines.
Turbines have blades that are rotated by the fluid flow, causing a shaft to spin and generate power.
The mechanical energy produced by turbines can be used to drive generators or other machinery.
Q11. What is transformer
A transformer is a device that transfers electrical energy between two or more circuits through electromagnetic induction.
Consists of two coils of wire, known as primary and secondary coils
Primary coil is connected to a power source, while secondary coil is connected to the load
Works on the principle of electromagnetic induction to change voltage levels
Used to step up or step down voltage levels in electrical systems
Examples include power transformers used in electrical subst...read more
Q12. What is resistance
Resistance is the opposition to the flow of electric current in a material.
Resistance is measured in ohms (Ω).
It is caused by collisions between electrons and atoms in a material.
Materials with high resistance are insulators, while materials with low resistance are conductors.
Resistance can be calculated using Ohm's Law: R = V/I, where R is resistance, V is voltage, and I is current.
Q13. What is power factor
Power factor is a measure of how effectively electrical power is being used in a circuit.
Power factor is the ratio of real power (kW) to apparent power (kVA) in an electrical circuit.
It indicates how efficiently power is being converted into useful work.
A power factor of 1 (or 100%) means all the power is being used effectively, while a power factor of 0 means none of the power is being used efficiently.
Power factor can be improved by using power factor correction devices lik...read more
Q14. What is DC motor
A DC motor is a type of electric motor that runs on direct current electricity, converting electrical energy into mechanical energy.
DC motors have a rotating armature and a stationary field magnet
They operate based on the principle of Lorentz force
Common types include brushed and brushless DC motors
DC motors are widely used in various applications such as robotics, electric vehicles, and industrial machinery
Q15. What is earthing
Earthing is the process of connecting electrical equipment to the earth to prevent electric shocks and ensure safety.
Earthing provides a path for fault currents to flow safely into the ground.
It helps in protecting equipment and individuals from electrical faults.
Earthing reduces the risk of fire hazards in electrical systems.
Types of earthing include plate earthing, pipe earthing, and rod earthing.
Proper earthing is essential in electrical installations to ensure safety and ...read more
Q16. What is contactor
A contactor is an electrical device used to switch an electrical circuit on or off.
Contactor is typically used in applications where high current needs to be controlled, such as in industrial machinery.
It consists of a coil which when energized creates a magnetic field that pulls in a set of contacts to make or break the circuit.
Contactor can be controlled manually or automatically through a control system.
Common examples of contactors include motor starters and lighting cont...read more
Q17. Types of transformer
Types of transformers include step-up, step-down, isolation, autotransformer, and distribution transformers.
Step-up transformer increases voltage levels
Step-down transformer decreases voltage levels
Isolation transformer provides electrical isolation between primary and secondary windings
Autotransformer has a single winding with multiple taps for different voltage levels
Distribution transformer is used to supply power to residential and commercial areas
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