1.What is the size of the recommended compressor CFM? Where it can be used?

Ans:⇢

It is generally used in spray painting of very small areas. It can be used where painting with brush is very difficult. thus to improve the rate of painting the spray painting is used as this method is very fast and efficient. Usually reciprocating compressors are used but size depends on requirements.

2.What is the range of engine efficiency in case of two stroke engine?

Ans:⇢

The two stroke engines have very high range to be compared to the four stroke engines. Because power stroke is generated every two revolution while in four stroke, power stroke is generated every four revolutions.

3.What do you understand by CC of engine?

Ans:⇢

The meaning of CC is cubic centimeters. It represents the total volume of the engine cylinder. This reflects that the engines with more CC can generate more powers than the other engines. CC can also be related as inversely proportional to the fuel consumption.

4.What is back compressor in engines?

Ans:⇢

Back compression means the compression capability of the engine. An diesel engine can compress at the ratio of 14:1 to as high as 25:1. Thus the higher compression leads to better efficiency of the engine. Thick black smoke is emitted when the engine’s compression is reduced which leads to the deformed ead-gasket lead into crankcase.

5.How air conditioners work in cars?

Ans:⇢

Air conditioners are based on the principles of evaporation and condensation and then compression and expansion. The hot air of the car is removed by the process of evaporation and then the condensation of the evaporated air takes places which is then further compressed by the compressor and then finally expanded to us in the form of cold breeze. Somehow, Air conditioning reduces the average of the car, as the energy is required to remove the hot air and then compression and expansion.

6.What are three methods of heat transfer?

Ans:⇢

Three methods of heat transfer are conduction, convection and radiation. Conduction: The transfer of energy by collisions between the atoms and molecules in a material. Convection: Transfers heat when particles move between objects or areas that differ in temperature. Radiation: The transfer of energy by waves.

7.Why the plastic materials used in the screwdriver\'s handles?

Ans:⇢

Due to non-conducting nature of plastic, it is widely used for the electricity purposes. Moreover, plastic is cheap and strong so it is less prone to damage. Furthermore, plastic does not bend and does not slips from the users hands.

8.Does diesel engine powered automobile use unit pump and unit injector?

Ans:⇢

In the case of the engines powered by diesel fuel supply systems, unit pump and unit injector are operated by camshaft and thus pressure of injected fuel depends on engine speed. Whereas,in common rail systems it is independent of engine speed.

9.If we use gasoline in diesel engine, what will happen?

Ans:⇢

Adding gasoline to the diesel engine may blast off the engine. Compression ratio of the petrol engine is 6 to 10 and diesel engine is 15 to 22. Thus gasoline will get very highly compressed and might result in blast off engine.

10.What is octane number and cetane number?

Ans:⇢

Octane number can be defined as the percentage, by volume, of iso-octane in the mixture of iso-octane and h-heptane. It is the measure of rating of SI engine. While cetane number can be defined as the percentage,by volume, of n-cetane in the mixture of n-cetane and alpha methyl naphthalene. It is the measure of rating of CI engine.