Heat and Thermodynamics

Problems

1. A boiler has 2 cm thick plates and exposes a surface of 2 sq m to the furnace. The temperature of the outside face is kept at 105°C. If the conductivity of the metal is 0.2 and the latent heat of steam is 540 calories per gm, find how much steam is generated in one hour?

    

   Ans. 66.7 kg

2. A steady stream of water is flowing at the rate of 500 gm a minute through a glass tube 30 cm long, 1 cm in external diameter are 8 mm in bore, the outside of which is surrounded by steam at a pressure of 760 mm of Hg which raises the temperature from 20°C to 30°C as it passes through the tube. Find the thermal conductivity of glass.

    

   Ans. 0.001315 cgs unit

3. Calculate approximately the heat passing out per minute through the walls and windows of a room ...