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What would happen if compressor is removed from the refrigerator?

Simply, refrigerator would STOP! but why? 

To answer this question, one need to know the Second law of thermodynamics (Clausius Statement) which states "It is impossible to construct a heat pump which continuously takes away the heat from low temperature region to high temperature region without taking any external work". 

Here, heat pump is our refrigerator which keep on throwing heat from low temperature environment to room temperature. As per the above statement, external work is must to run the refrigerator. That external work is represented by "Compressor".

Second thing, to have heat transfer from evaporator to condenser, you need to  change the phase of the substance. The change of phase absorb or liberate the heat depending on the phase change. Thus, heat of food can be transferred to condenser by changing the liquid phase refrigerant to vapor phase in evaporator and this heat is rejected at condenser at room temperature. This task is performed by compressor by changing the pressure of the refrigerant.

Why overall efficiency of thermal power plant is very low?

Are you wondering why overall efficiency of thermal power plant is very low? Reason?

The major part of the electricity that world is producing nowadays comes from Thermal Power Plant (which works on Rankine Cycle or Modified Rankine Cycle).

The principal parts of the Thermal Power Plants are

  • Boiler (to generate steam from water)
  • Turbine (where the steam expands and produces the work in form of rotation of shaft which in turn rotate the generator)
  • Condenser (where major part of heat is rejected to convert steam into water for reuse)
  • Feed Pump (to pump back the feed water to boiler for steam conversion) 
All parts except the condenser have 80 % to 90 % efficiency. The only condenser has 50% efficiency. 

Overall Efficiency: Multiplication of all efficiency of plant's principal parts
Thus overall efficiency comes down to 30 % - 40 %

How to write an abstract for technical report or article or paper?

If you are an engineer and working in industry or academics, you need to submit technical report or research paper to express the findings and working of stuffs.

An Abstract is an important element of any technical report or any research paper/article. It is something which people normally prefer to read before taking a look at the whole article. The abstract must contain the enough information which highlights and give the complete essence of the article. 

Normally abstract should deliver objectives of the research, methods that one has used for research, key results obtained and a clear and concise conclusion. 

The abstract should contain minimum 100 to 200 words. The content of the abstract should be clear and concise. 

It should highlight the main objectives and motivation of the research. Do not write an equation and related stuff in it. 

Avoid putting references in an abstract. One should not use in this 'paper' or 'article' but use 'research' or 'investigation'. 

The abstract must have enough information which develops the interest to read the full paper or article.

Tips for GPSC Interview for lecturer and assistant professor

These are the tips which can be helpful to clear the GSPC personal interview for lecturer and assistant professor
  1. Have confidence in your answer while you are asked to speak about yourself. This is normally very first question asked by chairman of interview "Tell me about yourself". Make answer ready in advance. Speak your full name, age, qualification with college and university,current job.
  2. Now when you are asked about your job, give positive aspects of job.
  3. Why do you want to do teaching job? Why not current job? Do not say I am not enjoying the current job but say, "I love teaching and this changes lives of people. I want to impact the life of many by teaching job. This job is respectful job"
  4. Always ready with two or three favorite subjects. 
  5. Prepare DEMO lecture that will be most probably asked to deliver. 
  6. SAY "NO" IF YOU ARE NOT VERY SURE ABOUT QUESTION'S ANSWER. IF YOU GIVE WRONG ANSWER THEY WILL TRAP YOU AND ULTIMATELY TIME AND YOUR REPUTATION WILL BE WASTED. Just say 'No' and pass the question. New question might be familiar to you. This will have impact of honesty on interviewer. 
  7. DO NOT ARGUE. DO not hurt them by saying I AM right even though they are wrong. They just make sure about your character.