Mechanical Engineering Interview Questions with answers

Mechanical Engineering Interview Questions with answers

1. What is the difference between Technology and Engineering? 

Ans. Engineering is application of
science. Technology shows various
methods of Engineering. A bridge can be
made by using beams to bear the load,by
an arc or by hanging in a cable; all
shows different technology but comes
under civil engineering and science
applied is laws of force/load
distribution.
 

2. How to Measure Temperature in Wet Bulb Thermometer?
 

Ans. Wet bulb temperature is measured
in a wet bulb thermometer by covering
the bulb with a wick and wetting it with
water. It corresponds to the dew point
temperature and relative humidity.
 

3. What are the Advantages and Disadvantages of using LPG in Car?
 

Ans. Advantages
1. Complete combustion
2. Fuel saving
3. Homogenous combustion
Disadvantages
1. As complete combustion is
occurring ,more heat liberated,not
advised for long journey, engine will be
over heated 2. Installation is difficult
3. Reduce engine life efficiency
 

4. What is the difference between Speed and Economic Speed?
 

Ans. The rated speed tells us about the
maximum speed which can be achieved by
a vehicle or some other machine but the
economical speed means the speed limit
at which the machine works efficiently
with least consumption of fuel.eg-in
normal bikes(not racing),the max.speed
limit shown on speedometer is upto 120
kmph but companies always advice their
customers to drive such bikes at around
60 kmph to have maximum mileage.
 

5. What is Powder Technology?
 

Ans. Powder technology is one of the
ways of making bearing material. In this
method metals like bronze, Al, Fe are
mixed and compressed to make an alloy.
 

6. State all the laws of Thermodynamics?
 

Ans. There are three laws of the
thermodynamics. First Law: Energy can
be neither created nor destroyed. It
can only change forms. In any process
in an isolated system, the total energy
remains the same. Second Law: When
two isolated systems in separate but
nearby regions of space, each in
thermodynamic equilibrium in itself, but
not in equilibrium with each other at
first, are at some time allowed to
interact, breaking the isolation that
separates the two systems, and they
exchange matter or energy, they will
eventually reach a mutual
thermodynamic equilibrium. The sum of
the entropies of the initial, isolated
systems is less than or equal to the
entropy of the final exchanging
systems. In the process of reaching a
new thermodynamic equilibrium, entropy
has increased, or at least has not
decreased. Third Law: As temperature
approaches absolute zero, the entropy of
a system approaches a minimum.