What is the difference between the steady state and unsteady state of heat transfer?

What are the applications of heat transfer study? Give some suitable examples.

Natural convection in water in lakes plays an important role in saving the lives of fishes when the atmospheric temperature falls below O°C. Comment.

What is Fourier's law of heat conduction What are the assumptions made for Fourier's law of heat conduction?

A plane wall, 20 cm thick, has a thermal conductivity given by the following relation:

K 2t 0.005 T

where T is temperature in Kelvin. If two surfaces of the wall are at 150°C and 50°C,determine the rate of heat transfer for a wall of 3 m x 5 m.

A hot plate 1 m x 2 m is maintained at 320°C. Air at 20°C moves over the plate. If h 40 watts/m^2°C, find the rate of heat transfer.

Derive an expression for the critical radius of insulation for a cylinder.

The walls of a house are 0·3 m thick and the total surface area of the walls is 100 m^2 . Thermal conductivity of the walls 1 Temperature of outside air is 37°C and inside air is 27°C. Heat transfer coefficients inside and outside are 20 and 10 respectively. Calculate the inside and outside wall temperature, and heat transfer rate through the walls.

What do you understand by fin effectiveness and fin efficiency

A composite slab has two layers of different materials with thermal conductivity and Find the equivalent thermal conductivity of the slab, if each layer has the same thickness.

What is Prandtl Number What is its significance?

The sun emits maximum radiation at A. u. Assuming the sun as a black body, find the surface temperature of the sun, and emissive power at that temperature.

Explain absorptivity, reflectivity and transmissivity.

Find the shape factors for the hemispherical surface and a plane surface as shown in Figure 1.

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