Steady two-dimensional heat conduction takes place in the body shown in the fig below. The normal temperature gradients over surface P and Q can be considered to be uniform. The temperature gradient ∂T/∂x= at surface Q is equal to 10 K/m. surfaces P and Q are maintained at constant temperatures as s

Consider one-dimensional steady state heat conduction along x-axis (0≤x≤L), through a plane wall with the boundary surfaces (x=0 and x=L) maintained at temperatures of 0 C and 100 C. Heat is generated uniformly throughout the wall. Choose the CORRECT statement. A. The direction of heat transfer

A gas filled tube has 2 mm inside diameter and 25 cm length. The gas is heated by an electrical wire of diameter 50 microns (0.05mm) located along the axis of the tube. Current and voltage drop across the heating element are 0.5 amps and 4 volts, respectively. If the measured wire and inside tube wa

Consider steady one-dimensional heat flow in a plate of 20 mm thickness with a uniform heat generation of 80 MW/m^3. The left and right faces are kept at constant temperatures of 160 C and 120 C respectively. The plate has a constant thermal conductivity of 200 W/m.K. The location of maximum temp wi

A fin has 5 mm diameter and 100 mm length. The thermal conductivity of fin material is 400 W/m.K. One end of the fin is maintained at 130 C and its remaining surface is exposed to ambient air at 30 C. if the convective heat transfer coefficient is 40 W/m^2.K, the heat loss (in W) from the fin is A.

A small copper ball of 5 mm diameter at 500 K is dropped into an oil bath whose temperature is 300 K. the thermal conductivity of copper is 400 W/m. K, its density 9000 kg/m3, and its specific heat 385 J/kg.K. if the heat transfer coefficient is 250 W/m2K and lumped analysis is assumed to be valid,

Biot number signifies the ratio of ____ A. convective resistance in the fluid to conductive resistance in the solid B. conductive resistance in the solid to convective resistance in the fluid C. inertia force to viscous force in the fluid D. buoyancy force to viscous force in the fluid

A composite wall, having a unit length normal to the plane of the paper, is insulated at the top and bottom as shown in the figure. It is comprised of four different materials A, B, C, and D. Dimensions are HA = HD = 3 cm, HB = HC = 1.5 cm, L1 = L3 = 0.05 m, L2 = 0.1 m The thermal conductivity of th

In a composite slab, the temperature at the interface (Tinter) between two materials is equal to the average of the temperatures at the two ends. Assuming steady one-dimensional heat conduction, which of the following statements is true about the respective thermal conductivities? A. 2K1=K2 B. K1=

Heat flows through a composite slab, as shown below. The depth of the slab is 1 m. the k values are in W/m.K. The overall thermal resistance in K/W is ________ A. 17.2 B. 21.9 C. 28.6 D. 39.2

The building has to be maintained at 21 C (dry bulb) and 14.5 C (wet bulb). The dew point temp under these conditions is 10.17 C. The outside temp is −23 C (dry bulb) and internal and external surface heat transfer coefficients are 8 W/m^2.K and 23 W/m^2.K respectively. If the building wall has a th

A pipe of 25 mm outer diameter carries steam. The heat transfer coefficient between the cylinder and surrounding is 5 W/m^2K. It is proposed to reduce the heat loss from the pipe by adding insulation having a thermal conductivity of 0.05 W/m.K. Which one of the following statements is TRUE? A. Th