Heat Transfer (3151909) MCQs

MCQs of Conduction

Showing 1 to 10 out of 36 Questions
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1.

Thermal conductivity is maximum for which substance

(a)

Silver
(b)

Ice
(c)

Aluminum
(d)

Diamond
Answer:

Option (d)

2.

Fourier law of heat conduction is best represented by

(a)

Q = -k A (d T /d x)
(b)

Q = k A (d x/d T)
(c)

Q = -k A 
(d)

Q = k (d T/d x)
Answer:

Option (a)

3.

The negative sign in the Fourier heat conduction equation indicates

(a)

Heat always flow is in the direction of positive temperature gradient
(b)

Heat always flow in the direction of negative temperature gradient
(c)

No heat flow is there
(d)

Data is insufficient
Answer:

Option (b)

4.

“Thermal conductivity represents the amount of heat conducted across the unit area when a temperature difference of one kelvin”.

(a)

TRUE
(b)

FALSE
Answer:

Option (b)

5.

Which of the following is the unit of thermal resistance?

(a)

°C/kcal
(b)

hour degree
(c)

s °C/kcal
(d)

°C/W
Answer:

Option (d)

6.

The temperature distribution in a large thin plate with uniform surface temperature will be (Assume steady-state condition)

(a)

Logarithmic
(b)

Hyperbolic
(c)

Parabolic
(d)

Linear
Answer:

Option (d)

7.

Let us assume two walls of the same thickness and cross-sectional area having thermal conductivities in the ratio 1/2. Let us say there is the same temperature difference across the wall faces, the ratio of heat flow will be

(a)

1
(b)

1/2
(c)

2
(d)

4
Answer:

Option (b)

8.

The thermal resistance for heat conduction through a spherical wall is

(a)

(r2-r1)/4πkr1r2
(b)

(r2-r1)/3πkr1r2
(c)

(r2-r1)/πkr1r2
(d)

(r2-r1)/2πkr1r2
Answer:

Option (a)

9.

Unit of thermal diffusivity is

(a)

m²/hr
(b)

m²/hr °C
(c)

kcal/m² hr
(d)

kcal/m. hr °C
Answer:

Option (a)

10.

The unit of overall coefficient of heat transfer is

(a)

W/m
(b)

W/mK
(c)

W/m²K
(d)

W/m²
Answer:

Option (c)

Showing 1 to 10 out of 36 Questions
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