In counter flow heat exchangers_________________?

A. both the fluids at inlet (of heat ex¬changer where hot fluid enters) are in their coldest state
B. both the fluids at inlet are in their hot¬test state
C. both the fluids .at exit are in their hottest state
D. one fluid is in hottest state and other in coldest state at inlet
E. any combination is possible depending on design of heat exchanger

True one-dimensional flow occurs when_________________?

A. the direction and magnitude of the veiocity at all points are identical
B. the velocity of successive fluid par-ticles, at any point, is the same at suc-cessive periods of time
C. the magnitude and direction of the velocity do not change from point to point in the fluid
D. the fluid particles move in plane or parallel planes and the streamline pat-terns are identical in each plane
E. velocity, depth, pressure etc. change from point to point in the fluid flow

Two dimensional flow occurs when________________?

A. the direction and magnitude of the velocity at all points are identical
B. the velocity of successive fluid particles, at any point, is the same at successive periods of time
C. the magnitude and direction of the velocity do not change from point to point in the fluid
D. the fluid particles move in plane or parallel planes and the streamline pat-terns are identical in each plane
E. velocity, depth, pressure, etc. change from point to point in the fluid flow

Uniform flow occurs when_____________________?

A. the direction and magnitude of the velocity at all points are identical
B. the velocity of successive fluid paiticles, at any point, is the same at successive periods of time
C. the magnitude and direction of the velocity do not change from point to point in the fluid
D. the fluid particles move in plane or parallel planes and the streamline pat-terns are identical in each pleasure
E. velocity, depth, pressure, etc. change from point to point in the fluid flow

Uniform flow occurs when ___________________?

A. the flow is steady
B. the flow is streamline
C. size and shape of the cross section in a particular length remain constant
D. size and cross section change uniformly along length
E. flow occurs at constant fate

Free air is the air at________________?

A. atmospheric conditions at any specific location
B. 20°C and 1 kg/cm2 and relative humidity of 36%
C. 0°C and standard atmospheric conditions
D. 15°C and 1 kg/cm2
E. 25°C, 1 kg/cm2 and relative humidity of 50%.

According of Kirchhoff’s law______________________?

A. radiant heat is proportional to fourth power of absolute temperature
B. emissive power depends on temperature
C. emissive power and absorptivity are constant for all bodies
D. ratio of emissive power to absorptive power is maximum for perfectly black body
E. ratio of emissive power to absorptive power for all bodies is same and is equal to the emissive power of a perfectly black body

According to Prevost theory of heat exchange ___________________?

A. it is impossible to transfer heat from low temperature source to t high temperature source
B. heat transfer by radiation requires no medium
C. all bodies above absolute zero emit radiation
D. heat transfer in most of the cases takes place by combination of conduction, convection and radiation
E. rate of heat transfer depends on thermal conductivity and temperature difference

Auto-ignition temperature is____________________?

A. minimum temperature to which oil is heated in order to give off inflammable vapours in sufficient quantity to ignite momentarily when brought in contact with a flame
B. temperature at which it solidifies or congeals
C. that at which it catches fire without external aid
D. indicated by 90% distillation temperature, i.e., when 90% of sample oil has distilled off
E. indicated by 50% distillation temperature

Volatility of diesel fuel oil is_________________?

A. minimum temperature to which oil is heated in order to give off inflammable vapours in sufficient quantity to ignite momentarily when brought in contact with a flame
B. temperature at which it solidifies or congeals
C. it catches fire without external aid
D. indicated by 90% distillation temperature, i.e., when 90% of sample oil has distilled off
E. temperature at which it flows easily

An alien bolt is___________________?

A. self locking bolt
B. same as stud
C. provided with hexagonal depression in head
D. used in high speed components
E. provided with countersunk head

Allen bolts are___________________?

A. self locking bolts
B. designed for shock load
C. used in aircraft application
D. provided with hexagonal depression in head
E. uniform strength bolts

A bolt___________________?

A. has a head on one end and a nut fitted to the other
B. has head at one end and other end fits into a tapped hole in the other part to be joined
C. has both the ends threaded
D. is provided with pointed threads
E. requires no nut

Inter cooling in compressors__________________?

A. cools the delivered air
B. results in saving of power in compressing a given volume to given pressure
C. is the standard practice for big compressors
D. enables compression in two stages
E. prevents compressor jacket running very hot