1
GATE ME 1999
+2
-0.6
It is proposed to coat a $$1mm$$ diameter wire with enamel paint $$\left( {k\,\,\,\, = 0.1W/m} \right.$$ - $$\left. K \right)$$ to increase heat transfer with air. If the air side heat transfer co-efficiency is $$100$$ $$W/{m^2}K,$$ the optimum thickness of enamel paint should be
A
$$0.25$$ $$mm$$
B
$$0.5$$ $$mm$$
C
$$1$$ $$mm$$
D
$$2$$ $$mm$$
2
GATE ME 1998
+2
-0.6
The temp variation under steady heat conduction across a composite slab of two materials with thermal conductivies $${K_1}$$ and $${K_2}$$ is shown in fig. then, which one of the following statements holds? A
$${K_1} > {K_2}$$
B
$${K_1} = {K_2}$$
C
$${K_1} = 0$$
D
$${K_1} < {K_2}$$
3
GATE ME 1996
+2
-0.6
For a current carrying wire of $$20$$ $$mm$$ diameter and having $$k=0.5W/mK$$ is exposed to air $$\left( {h = 20W/{m^2}K} \right),$$ maximum heat dissiption occurs when thickness of insulation is
A
$$30$$ $$mm$$
B
$$25$$ $$mm$$
C
$$20$$ $$mm$$
D
$$15$$ $$mm$$
4
GATE ME 1991
Subjective
+2
-0
Match the property with their units

Property
$$A.$$ Bulk modulus
$$B.$$ Thermal conductivity
$$C.$$ Heat transfer coefficient
$$D.$$ Heart flow rate

Units
$$1.$$ $$W/s$$
$$2.$$ $$N/{m^2}$$
$$3.$$ $$N/{m^3}$$
$$4.$$ $$W$$
$$5.$$ $$W/mK$$
$$6.$$ $$W/{m^2}K$$

GATE ME Subjects
Engineering Mechanics
Machine Design
Strength of Materials
Heat Transfer
Production Engineering
Industrial Engineering
Turbo Machinery
Theory of Machines
Engineering Mathematics
Fluid Mechanics
Thermodynamics
General Aptitude
EXAM MAP
Joint Entrance Examination