The process of heat transfer during the re-entry of satellites and missiles, at very high speeds, into earth?s atmosphere is known as

Reentry occurs when a person leaves his or her social system for a period of time and then returns. Which situation below best describes Reentry ?

A

When he is offered a better paying position, Jacob leaves the restaurant he manages to manage a new restaurant on the other side of town.

B

Catherine is spending her junior year of college studying abroad in France.

C

Malcolm is readjusting to civilian life after two years of overseas military service.

D

After several miserable months, Sharon decides that she can no longer share an apartment with her roommate Hilary.

When an object enters earths atmosphere, it travels ----

A

very repidly

B

in a rapid manner

C

fastly

D

rapidly

The scales form in heat exchanges after a period of operation and provide additional resistance to heat transfer with some heat transfer coefficient . The reciprocal of this scale heat transfer coefficient is called .

A

scaling factor

B

forming factor

C

resisting factor

D

fouling factor

Extended heat transfer surface like fins are used to increase the heat transfer rate. Fin efficiency is defined as the ratio of heat transferred across the fin surface to the theoretical heat transfer across an equal area held at the

A

Surrounding temperature

B

Average temperature of the fin

C

Temperature of the fin end

D

Constant temperature equal to that of the base

Satellites burn off during re-entry to earth's atmosphere, because of the

A

Combustion with air

B

Gravitational pull by earth

C

Friction with earth's atmosphere

D

Loss in weight of the satellite

For shell and tube heat exchanger, with increasing heat transfer area, the purchased cost per unit heat transfer area

A

Increases

B

Decreases

C

Remains constant

D

Passes through a maxima

Air is to be heated by condensing steam. Two heat exchangers are available (i) a shell and tube heat exchanger and (ii) a finned tube heat exchanger. Tube side heat transfer area are equal in both the cases. The recommended arrangement is

A

Finned tube heat exchanger with air inside and steam outside

B

Finned tube heat exchanger with air outside and steam inside

C

Shell and tube heat exchanger with air inside tubes and steam on shell side

D

Shell and tube heat exchanger with air on shell side and steam inside tubes

A and B go cycling in the same direction with speeds of 6 km /hr and 12 km/hr. A car from behind passes them in 9 and 10 seconds respectively . What is the speeds of the car?

A

22 km/hr

B

33 km/hr

C

66 km/hr

D

44 km/hr

In an interphase heat transfer process, the equilibrium state corresponds to equality of temperature in the two phases, while the condition for equilibrium in an interphase mass transfer process is equality of

A

Concentrations

B

Chemical potentials

C

Activity co-efficients

D

Mass transfer co-efficients

For turbulent flow in a tube, the heat transfer co-efficient is obtained from the Dittus-Boelter correlation. If the tube diameter is halved and the flow rate is doubled, then the heat transfer co-efficient will change by a factor of

A

1

B

1.74

C

6.1

D

37

The process of heat transfer during the re-entry of satellites and missiles, at very high speeds, into earth?s atmosphere is known as

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