0
0.5
1
5
✅ The correct answer is option C.
Heat Transfer MCQs
Boiling point elevation of a solution of NaOH
Increases rapidly with temperature rise
Is almost independent of temperature
Is almost independent of pressure
Both B and C
✅ The correct answer is option D.
At constant temperature, the thermal conductivities of gases __________ with rise in pressure.
Decrease
Increase
Remain unchanged
May increase or decrease; depends on the pressure
✅ The correct answer is option A.
Which has the lowest Prandtl number?
Liquid metal
Aqueous solution
Water
Lube oil
✅ The correct answer is option A.
Out of 100 kcal/second of incident radiant energy on the surface of a thermally transparent body, 300 kcal/second is reflected back. If the transmissivity of the body is 0.25, the emissivity of the surface will be
0.35
0.45
0.55
0.85
✅ The correct answer is option B.
In counter flow compared to parallel flow,
LMTD is greater
Less surface area is required for a given heat transfer rate
Both A and B
More surface area is required for a given heat transfer rate
✅ The correct answer is option C.
It is not preferable to use superheated steam in evaporators, because of its very
High temperature
High pressure
Low film co-efficient
None of these
✅ The correct answer is option C.
Thermal conductivities of most of the liquids __________ with rise in temperature.
Increases
Decreases
Remains unchanged
May increase or decrease; depends on the liquid
✅ The correct answer is option B.
Which of the following has the highest thermal conductivity?
Brick
Air
Water
Silver
✅ The correct answer is option D.
__________ chart is known as transient heat conduction chart.
Dirhing’s
Heisler’s
Mollier’s
Cox
✅ The correct answer is option A.