Depending upon the behavior of condensate up on the cooled surface, the condensation process are classified into how many distinct modes?

Which are the correct statements? (a) Film condensation usually occur on oily surface. (b) Temperature of condensate gradually increases towards the liquid-vapour interface. (c) Suitable coating is used to promote dropwise condensation. (d) Dropwise condensation gives lower heat transfer rate than film condensation.

A

(a), (d)

B

(e), (d)

C

(a),(b)

D

(b), (c)

Consider the following statements (i) If a condensing liquid does not wet a surface, then drop wise condensation will not take place on it (ii) Drop wise condensation gives a higher transfer rate than film wise condensation (iii) Reynolds number of condensing liquid is based on its mass flow rate (iv) Suitable coating or vapor additive is used to promote film wise condensation Identify the correct statement

A

i and ii

B

ii, iii and iv

C

iv only

D

i, ii and iii

Statement 1: Film-type condensation has a higher heat transfer co-efficient than drop-wise condensation. Statement 2: Drop-wise condensation is easier to maintain than Film-type condensation

A

True, False

B

True, True

C

False, False

D

False, True

Statement (I): Piston temperature profiles near full load are flattened in case of liquid cooled engines whereas for air cooled engines temperature profiles are steeper. Statement (II): The piston temperature profiles are different in nature for liquid cooled and air cooled engines because of the different values of heat capacities.

A

Both Statement I) and Statement II) are individually true and Statement II) is the correct explanation of Statement I)

B

Both Statement I) and Statement II) are individually true but Statement II) is not the correct explanation of Statement I)

C

Statement I) is true but Statement II) is false

D

Statement I) is false but Statement II) is true

With eleven distinct consonants and five distinct vowels, how many distinct six letter words can be formed if middle two positions are occupied by vowels (may be repeated) and first two and last two positions are occupied by consonants (all distinct) ?

A

168000

B

178000

C

188000

D

198000

Justice is regarded as
1. Distinct from benevolence
2. Distinct from charity
3. Distinct from ethics
4. Distinct from awareness
Select the correct answer:

A

1 and 2

B

2 and 3

C

3 and 4

D

2 and 4

Rearrange the parts of the sentence in correct order. P: This discipline is characterized by several concepts and approaches that are used by psychologists in understanding human behavior.
Q: The field of psychology can be described as a discipline that focuses on the study of mind and behavior.
R: Some of the most common psychological concepts that are used to modify or change an individuals behavior include operant conditioning, positive and negative punishment, and positive and negative reinforcement.
S: Since psychology is a broad field, psychologists not only use these concepts and approaches but also conduct scientific research that enables them to understand
human behavior.

A

QPSR

B

PQRS

C

RSQP

D

SRPQ

A two pass surface condenser is required to handle the exhaust from a turbine developing 15 MW with specific steam consumption of 5 kg/k W h. The quality of exhaust steam is 0.9, the condenser vacuum is 66 cm of mercury while the bar meter reads 76 cm of mercury. The condenser tubes are 28 mm inside diameter, 4 mm thick and water flows through tubes with a speed of 3 m/s and inlet temperature 20 degree Celsius. All the steam is condensed, the condensate is saturated water and temperature of cooling water at exit is 5 degree Celsius less than the condensate temperature. Assuming that overall coefficient of heat transfer is 4 k W/m2 degree, determine the mass of cooling water circulated

A

746.13 kg/s

B

646.13 kg/s

C

546.13 kg/s

D

446.13 kg/s

Saturated steam is allowed to condense over a vertical flat surface and the condensate film flows down the surface. The local coefficient of heat transfer for condensation

A

Remains constant at all heights of the surface

B

Decreases with increasing distance from the top of the surface

C

Increases with increasing thickness of film

D

Increases with increasing temperature differential between the surface and vapour

Identify the correct set. Set Physical Changes Chemical Changes A Ozone formation from Oxygen, Condensation Rusting, Burning of candle B Evaporation, Alloy formation Rusting, Curd formation C Condensation, Evaporation Combustion, Galvanization D Galvanization, Alloy formation Crystallization, Condensation

A

B

C

D

Depending upon the behavior of condensate up on the cooled surface, the condensation process are classified into how many distinct modes?

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