Mechanical Engineering
2020 · Paper 2
Take it one question at a time. Try an answer, then check your understanding.
Complete GATE ME 2020 Paper 2 overview, original pages and practice · Timed previous-paper practice
Questions 34–36 of 65. Imported answers require review unless explicitly marked reviewed.
Question 24
Open questionMENAT1 markNeeds review
In a furnace, the inner and outer sides of the brick wall (
W/m.K) are maintained at 1100°C and 700°C, respectively as shown in figure. The brick wall is covered by an insulating material of thermal conductivity
. The thickness of the insulation is 1/4th of the thickness of the brick wall. The outer surface of the insulation is at 200°C. The heat flux through the composite walls is 2500 W/m
. The value of
is ______ W/m.K (round off to one decimal place). 
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Open questionMENAT1 markNeeds review
If a reversed Carnot cycle operates between the temperature limits of 27°C and −3°C, then the ratio of the COP of a refrigerator to that of a heat pump (COP of refrigerator / COP of heat pump) based on the cycle is __________ (round off to 2 decimal places).
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Open questionMEMCQ2 marksNeeds review
The directional derivative of
at point
in the direction of vector
isYour answerChoose one option.
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