THERMAL CONDUCTIVITY OF FIN MATERIAL SHOULD BE LARGE WHICH OF THE A...
4.
Thermal conductivity of fin material should be large
Which of the above statements are correct?
(a) 1, 2 and 3
(b) 1, 2 and 4
(c) 2, 3 and 4
(d) 1, 3 and 4
IES-16. Assertion (A): In a liquid-to-gas heat exchanger fins are provided in the
gas side.
[IES-2002]
Reason (R): The gas offers less thermal resistance than liquid
(a) Both A and R are individually true and R is the correct explanation of A
(b) Both A and R are individually true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
IES-17. Assertion (A): Nusselt number is always greater than unity.
Reason (R): Nusselt number is the ratio of two thermal resistances, one
the thermal resistance which would be offered by the fluid, if it was
stationary and the other, the thermal resistance associated with
convective heat transfer coefficient at the surface.
[IES-2001]
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IES-18. Extended surfaces are used to increase the rate of heat transfer. When
the convective heat transfer coefficient h = mk, the addition of
extended surface will:
[IES-2010]
(a)
Increase the rate of heat transfer
(b)
Decrease the rate of heat transfer
(c)
Not increase the rate of heat transfer
(d)
Increase the rate of heat transfer when the length of the fin is very large
IES-19. Addition of fin to the surface increases the heat transfer if
hA KP
/
is:
(a) Equal to one
(b) Greater than one
[IES-1996]
(c) Less than one
(d) Greater than one but less than two
IES-20. Consider the following statements pertaining to heat transfer through
fins: [IES-1996]