10+ SELI Tunnelling India Interview Questions and Answers

2 stroke engines have a power stroke in each revolution, while 4 stroke engines have a power stroke in every other revolution.

• 2 stroke engines have a simpler design and are lighter than 4 stroke engines.

• 2 stroke engines have a higher power-to-weight ratio compared to 4 stroke engines.

• 4 stroke engines are more fuel-efficient and produce less pollution than 2 stroke engines.

• Examples of 2 stroke engines include chainsaws, motorcycles, and outboard motors, while examples of 4 str...read more

Pump efficiency is the ratio of the output power to the input power of a pump.

• Efficiency is important for reducing energy consumption and operating costs.

• It is calculated by dividing the pump's output power by its input power.

• Factors that affect pump efficiency include impeller design, flow rate, and head.

• A more efficient pump will require less energy to achieve the same flow rate and head.

• Regular maintenance and proper sizing can improve pump efficiency.

A centrifugal pump is a mechanical device that uses centrifugal force to transport fluids.

• It consists of an impeller that rotates to create a flow of fluid.

• The fluid enters the pump through the center of the impeller and is thrown outward by centrifugal force.

• The fluid then exits the pump through a discharge nozzle.

• Centrifugal pumps are commonly used in industries such as oil and gas, chemical, and water treatment.

• Examples of centrifugal pumps include water pumps, sewage pump...read more

Break efficiency is the ratio of actual braking power to the theoretical braking power.

• It is a measure of how effectively a brake system can stop a vehicle.

• It is expressed as a percentage.

• Factors affecting break efficiency include brake pad material, rotor size, and temperature.

• A higher break efficiency means the brake system is more effective at stopping the vehicle.

• Break efficiency can be calculated using the formula: (Actual braking power / Theoretical braking power) x 100...read more

Poison ratio is the ratio of lateral strain to longitudinal strain when a material is subjected to stress.

• It is also known as transverse strain ratio or lateral strain coefficient.

• It is a measure of the deformation of a material under stress.

• It is calculated as the negative ratio of lateral strain to longitudinal strain.

• For most materials, the poison ratio ranges from 0.25 to 0.35.

• Rubber has a very low poison ratio, while steel has a high poison ratio.

An engine is a machine that converts energy into mechanical force or motion.

• Engines are used in various applications such as automobiles, aircraft, and power plants.

• They typically operate by burning fuel to generate heat, which is then converted into mechanical energy.

• Engines can be classified into different types, including internal combustion engines, steam engines, and electric motors.

• Examples of engines include car engines, jet engines, and steam locomotive engines.

Force is a physical quantity that can change the motion of an object.

• Force is measured in Newtons (N).

• It can be a push or a pull.

• Force can change the shape or size of an object.

• Examples of force include gravity, friction, and tension.

• Force is a vector quantity, meaning it has both magnitude and direction.

Strain is the deformation or change in shape of a material due to an applied force.

• Strain is a measure of how much a material deforms under stress.

• It is calculated as the change in length or shape of a material divided by its original length or shape.

• Strain can be either compressive or tensile, depending on the direction of the applied force.

• Examples of strain include stretching a rubber band, bending a metal rod, or compressing a spring.

Ductility is the ability of a material to deform under tensile stress without breaking.

• Ductility is a property of metals and alloys.

• It is measured by the percentage of elongation or reduction in cross-sectional area before fracture.

• Ductile materials can be drawn into wires or hammered into thin sheets.

• Examples of ductile materials include gold, silver, copper, and aluminum.

• Ductility is important in engineering applications where materials need to withstand stress without brea...read more

Bulk modules are pre-fabricated units used in construction and engineering projects.

• Bulk modules are pre-fabricated units that can be easily transported and assembled on-site.

• They are commonly used in construction and engineering projects to save time and reduce costs.

• Examples of bulk modules include pre-fabricated walls, floors, and roofs for buildings, as well as pre-fabricated piping and electrical systems for industrial plants.

• Bulk modules can be customized to meet specif...read more