30+ KoinBX Interview Questions and Answers

White fumes from automobile silencer are due to condensation of water vapor and unburnt fuel.

• During combustion, water vapor is produced as a byproduct.

• When the exhaust gases cool down in the silencer, the water vapor condenses and appears as white fumes.

• Unburnt fuel can also contribute to the white fumes.

• This is a normal phenomenon and nothing to worry about unless the fumes are excessive or have a strange odor.

The capacity of the battery is calculated based on the energy requirements and the discharge rate. The rating of the motor is determined by the power requirements and efficiency.

• Battery capacity is calculated by dividing the energy requirements by the discharge rate.

• Motor rating is determined by dividing the power requirements by the efficiency.

• Consider factors like voltage, current, and duration of operation when calculating capacity and rating.

• Example: For a battery with en...read more

Answering questions on Industrial Engineering and layouts

• Yes, I have taken a course on Industrial Engineering

• Different layouts include process layout, product layout, and fixed position layout

• Just in time is a manufacturing philosophy where materials are delivered just in time for production

• It aims to reduce inventory costs and increase efficiency

• For example, Toyota uses just in time manufacturing to reduce waste and improve production speed

A 4-speed synchromesh gearbox is a type of manual transmission commonly used in automobiles.

• Synchromesh gearbox allows for smoother shifting between gears

• Each gear has its own synchronizer ring to match the speed of the gear and the input shaft

• The gears are arranged in a specific order, typically in an H-pattern

• The driver must depress the clutch pedal to disengage the gears before shifting

• Commonly found in sports cars and high-performance vehicles

Parameters to consider for designing press fit assembly (hole and shaft)

• Tolerance of the hole and shaft

• Material properties of the hole and shaft

• Interference fit required

• Press fit force required

• Surface finish of the hole and shaft

• Assembly process and equipment

• Environmental conditions

• Design for disassembly

The larger radius of wheels at the back of tractors provides better traction and stability.

• Larger wheels at the back increase the tractors' pulling power and ability to carry heavy loads.

• The larger surface area of the wheels distributes the weight more evenly, reducing soil compaction.

• The increased radius helps in overcoming obstacles and rough terrains.

• The larger wheels also improve the tractors' stability and prevent tipping over.

• Examples: Tractors used in agriculture, cons...read more

The more efficient option is X due to its faster processing speed and lower energy consumption.

• Option X is more efficient because it has a higher processing speed.

• Option X consumes less energy compared to option Y.

• Option X provides better performance and productivity.

• Option Y may have certain advantages, but overall, option X is more efficient.

Diesel cycle is a constant pressure cycle while Otto cycle is a constant volume cycle.

• Diesel cycle uses compression ignition while Otto cycle uses spark ignition.

• Diesel cycle has a higher compression ratio than Otto cycle.

• Diesel cycle is used in diesel engines while Otto cycle is used in gasoline engines.

• Diesel cycle has a higher thermal efficiency than Otto cycle.

• Diesel cycle has a longer combustion duration than Otto cycle.

Emission norms are regulations that limit the amount of pollutants released into the environment by vehicles and industries.

• Emission norms are set by governments to reduce air pollution and protect public health.

• They specify the maximum amount of pollutants that can be emitted by vehicles and industries.

• Examples of pollutants include carbon monoxide, nitrogen oxides, particulate matter, and sulfur dioxide.

• Emission norms are becoming increasingly strict as the world becomes mo...read more

Exhaust gases are composed of various pollutants released from combustion of fuels.

• Exhaust gases contain carbon monoxide, nitrogen oxides, sulfur dioxide, particulate matter, and unburned hydrocarbons.

• Carbon monoxide is a poisonous gas that can cause headaches, dizziness, and even death.

• Nitrogen oxides contribute to smog and acid rain.

• Sulfur dioxide can cause respiratory problems and contribute to acid rain.

• Particulate matter can cause lung damage and other health problems.

• Un...read more

No, electric vehicles do not use gearbox as they have high torque at low speeds.

• Electric motors have a wide range of torque and can operate at low speeds without the need for a gearbox.

• Gearboxes add weight and complexity to the vehicle.

• Electric vehicles use a single-speed transmission or direct drive system.

• Examples of electric vehicles without gearbox are Tesla Model S, Nissan Leaf, and BMW i3.

Drags experienced by vehicles are forces that oppose motion and reduce speed.

• Air resistance or drag caused by air molecules colliding with the vehicle's surface

• Frictional drag caused by the vehicle's tires or wheels rubbing against the road surface

• Gravity drag caused by the vehicle's weight and the force of gravity

• Inertia drag caused by the vehicle's mass and resistance to changes in motion

• Examples include wind resistance when driving a car, rolling resistance when cycling, a...read more

Transmission transfers power from engine to wheels through a series of gears and shafts.

• Engine power is transferred to the transmission through the clutch.

• The transmission uses gears to adjust the speed and torque of the output shaft.

• The output shaft is connected to the driveshaft, which transfers power to the differential.

• The differential splits the power between the two wheels, allowing them to rotate at different speeds.

• The wheels are connected to the axles, which transfer...read more

Limited slip differential is a type of differential that limits the speed difference between two wheels on an axle.

• It allows for better traction and handling in slippery conditions

• It works by using a clutch or viscous fluid to transfer torque between the wheels

• Examples include the Torsen differential and the Quaife differential

Diesel engines use compression ignition while petrol engines use spark ignition.

• Diesel engines are more fuel-efficient than petrol engines.

• Petrol engines have higher power output than diesel engines.

• Diesel engines are more durable and have longer lifespan than petrol engines.

• Petrol engines are quieter and smoother than diesel engines.

• Examples of diesel engines include those used in trucks and buses while petrol engines are commonly used in cars and motorcycles.

CO and NOx emissions can be reduced by various methods.

• Using catalytic converters in vehicles

• Switching to cleaner fuels like natural gas or biofuels

• Implementing stricter emission standards for industries

• Using scrubbers in power plants to remove pollutants

• Promoting public transportation and carpooling

• Encouraging the use of electric vehicles

• Improving engine efficiency through design and maintenance

• Reducing idling time for vehicles

• Using renewable energy sources to power industri...read more

First angle projection and third angle projection are two methods of representing a 3D object on a 2D surface.

• First angle projection is commonly used in Europe and Asia, while third angle projection is commonly used in North America.

• In first angle projection, the object is placed between the viewer and the projection plane, while in third angle projection, the object is placed behind the projection plane.

• First angle projection is often considered more intuitive, while third a...read more

A 4 stroke engine works by completing four distinct stages - intake, compression, combustion, and exhaust.

• Intake: Fuel and air are drawn into the cylinder.

• Compression: The piston compresses the fuel-air mixture.

• Combustion: The spark plug ignites the mixture, causing an explosion.

• Exhaust: The piston pushes out the exhaust gases.

• This process repeats for every four strokes of the piston.

NOx emissions can be reduced by using low NOx burners, selective catalytic reduction, exhaust gas recirculation, and fuel switching.

• Use low NOx burners in combustion processes

• Implement selective catalytic reduction to convert NOx to nitrogen and water

• Use exhaust gas recirculation to reduce oxygen levels in combustion processes

• Switch to cleaner fuels such as natural gas or hydrogen

• Optimize combustion processes to reduce excess air and fuel consumption

A speed governor regulates the speed of an engine by controlling the fuel supply.

• Speed governor is a device that controls the speed of an engine.

• It regulates the fuel supply to the engine to maintain a constant speed.

• It works by sensing the engine speed and adjusting the fuel supply accordingly.

• There are different types of speed governors such as mechanical, hydraulic, and electronic.

• Examples of applications include generators, automobiles, and industrial machinery.

Emission consists of gases and particles released into the air by various sources.

• Emission can come from natural sources like volcanoes and wildfires, as well as human activities like transportation and industry.

• Common pollutants in emissions include carbon monoxide, nitrogen oxides, sulfur dioxide, and particulate matter.

• Emissions can have harmful effects on human health and the environment, including contributing to climate change and air pollution.

• Regulations and technolog...read more

Disc brakes are a type of braking system used in vehicles that use a flat, circular disc to slow or stop the vehicle.

• Disc brakes work by using calipers to squeeze brake pads against a rotor attached to the wheel.

• They are more efficient than drum brakes and provide better stopping power.

• Disc brakes are commonly used in high-performance vehicles and sports cars.

• They are also used in bicycles and motorcycles.

• Disc brakes require less maintenance than drum brakes and are less pron...read more

Electrical engineering is used in various parts of a car, including the engine, lighting, and entertainment systems.

• Electrical engineering is used in the car's engine management system to control fuel injection and ignition timing.

• The car's lighting system, including headlights, taillights, and interior lighting, is powered by electrical engineering.

• The entertainment system, including the radio and speakers, also relies on electrical engineering.

• Electric and hybrid cars rely ...read more

Turbocharger is a device that increases the efficiency of an engine by compressing air before it enters the combustion chamber.

• Turbochargers use exhaust gases to spin a turbine, which in turn drives a compressor to compress the air intake.

• This compressed air allows more fuel to be burned, resulting in increased power output.

• Turbochargers are commonly used in diesel engines and high-performance gasoline engines.

• Examples of cars with turbochargers include the Volkswagen Golf GT...read more

A clutch is a mechanical device that engages and disengages power transmission between two rotating shafts.

• A clutch is used in vehicles to connect the engine to the transmission.

• It allows the driver to change gears and control the power flow.

• When the clutch pedal is pressed, the clutch disc disengages from the flywheel, interrupting power transmission.

• Releasing the clutch pedal gradually engages the clutch, allowing power to be transferred.

• Clutches can be of various types, su...read more

An induction motor starts by creating a rotating magnetic field in the stator which induces a current in the rotor.

• The stator windings are energized with a three-phase AC supply

• This creates a rotating magnetic field in the stator

• The rotating magnetic field induces a current in the rotor

• The interaction between the stator and rotor magnetic fields causes the rotor to rotate

• The motor reaches its full speed when the rotor speed matches the speed of the rotating magnetic field

The condition of the frame shop is good.

• The frame shop is well-maintained and organized.

• All the equipment and tools are in good working condition.

• There is a sufficient stock of materials and supplies.

• The shop follows safety protocols and regulations.

• The employees are skilled and trained in frame fabrication techniques.

Draw Carnot cycle on T-S curve.

• Carnot cycle is a theoretical thermodynamic cycle.

• It consists of four reversible processes: isothermal expansion, adiabatic expansion, isothermal compression, and adiabatic compression.

• The cycle is represented on a T-S diagram.

• The area enclosed by the cycle represents the work done by the system.

• The efficiency of the cycle is given by (T1-T2)/T1, where T1 is the temperature of the hot reservoir and T2 is the temperature of the cold reservoir.

Least count of mm is the smallest measurement that can be read on a measuring instrument.

• It is important to know the least count of a measuring instrument to ensure accurate readings.

• It is usually mentioned on the instrument itself or in the user manual.

• For example, the least count of a Vernier caliper is 0.02 mm.

• The least count of a micrometer screw gauge is 0.01 mm.

Ductile failure is a type of material failure where the material stretches and deforms before breaking.

• Occurs in materials that can undergo plastic deformation

• Material stretches and deforms before breaking

• Common in metals like copper, aluminum, and steel

• Ductile materials are preferred in applications where deformation is expected

• Examples include wires, cables, and structural components

Methods to change speed of motor

• Using variable frequency drive (VFD)

• Changing the voltage applied to the motor

• Adjusting the resistance in the circuit

• Using a gearbox to change the output speed

• Using a pulley system to change the speed

• Using a servo motor with a controller

• Using a stepper motor with a controller

A turbo machine is a device that transfers energy between a fluid and a rotor, typically used in engines and turbines.

• Turbo machines include turbochargers, gas turbines, and steam turbines

• They are used to increase the efficiency and power output of engines

• Work by converting the kinetic energy of a moving fluid into mechanical energy

The engine starts when the ignition key is turned on, which sends an electrical signal to the starter motor.

• The ignition key is turned on, which sends an electrical signal to the starter motor

• The starter motor turns the engine's crankshaft

• Fuel and air are mixed in the engine's cylinders and ignited by the spark plugs

• The combustion process creates pressure that pushes the pistons, which turn the crankshaft

• The engine continues to run as long as fuel and air are supplied and the...read more