Q.1
##### If the radius of any current carrying conductor is less than the critical radius, then why the addition of electrical insulation will enable the wire to carry a higher current?
• a) The heat loss from the wire would decrease
• b) The heat loss from the wire would increase
• c) The thermal resistance of the insulation is reduced
• d) The thermal resistance of the conductor is increased
Q.2
• a) Air
• b) Water
• c) Plastic
• d) Rubber
Q.3
##### In MLTθ system (T time and θ temperature), what is the dimension of thermal conductivity?
• a) ML-1T-1θ-3
• b) MLT-1θ-3
• c) MLT-3θ-1
• d) MLT-2θ-1
Q.4
##### For conduction through a spherical wall with constant thermal conductivity and with inner side temperature greater than outer wall temperature in 1-D heat transfer, what is the type of temperature
• a) Linear
• b) Parabolic
• c) Hyperbolic
• d) Logarithmic
Q.5
• a) k2ρc
• b) 1/ρkc
• c) k/ρc
• d) ρc/k2
Q.6
##### A copper block and an air mass block having similar dimensions are subjected to symmetrical heat transfer from one face of the each block. The other face of the block will be reaching to the same temperature at a rate?
• a) Faster in air block
• b) Faster in copper block
• c) Equal in air as well as copper block
• d) Data in sufficient
Q.7
##### The outer surface of a long cylinder is maintained at constant temperature. The cylinder does not have any heat source. The temperatures in the cylinder will _________
• a) Increase linearly with radius
• b) Decrease linearly with radius
• c) Be independent of radius
• d) Vary logarithmically with radius
Q.8
##### A steam pipe is covered with two layers of insulating materials, with the better insulating material forming the outer. What is the effect on heat conducted if the two layers are interchanged?
• a) Will increase
• b) Will decrease
• c) Will remain unaffected
• d) May increase or decrease depending upon the thickness of each layer
Q.9
• a) 0.10 kW
• b) 0.15 kW
• c) 0.20 kW
• d) 0.25 kW
Q.10
• a) 45mm
• b) 60mm
• c) 75mm
• d) 90mm
Q.11
• a) 2q0/R
• b) 2q0
• c) q0/R
• d) 2q0/3R
Q.12
• a) 100°C
• b) 200°C
• c) 400°C
• d) 600°C
Q.13
##### As the temperature increases, the thermal conductivity of a gas ____________
• a) Increases
• b) Decreases
• c) Remain constant
• d) Increases up to a certain temperature and then decreases