A 1 m thick wall is made of concrete with a thermal conductivity of 1 W/m/K. There are temperature sensors on the wall’s surface and buried within the wall 1 cm from each surface. One set of temperature sensors shows the surface at 30 oC and the subsurface at 32 oC, while the other shows the surface at 40 oC and the subsurface at 35 oC. a. Is the wall heating up or cooling down? b. What’s the rate of change of thermal energy contained per unit area of wall? c. Would your answer change if the wall were 0.5 m thick?

Line joining liquid phase with liquid and solid phase mixture is known as: a) liquidus b) solidus c) tie line d) none of the mentioned

Apump is used to circulate hot water in a home heating system. water enters the well-insulated pump operating at steady state at a rate of 0.42 gal/min. the inlet pressure and temperature are 14.7 lbf/in.2, and 180°f, respectively; at the exit the pressure is 60 lbf/in.2 the pump requires 1/15 hp of power input. water can be modeled as an incompressible substance with constant density of 60.58 lb/ft3 and constant specific heat of 1 btu/lb or. neglecting kinetic and potential energy effects, determine the temperature change, in °r, as the water flows through the pump.

You are making beer. the first step is filling the glass carboy with the liquid wort. the internal diameter of the carboy is 15 in., and you wish to fill it up to a depth of 2 ft. if your wort is drawn from the kettle using a siphon process that flows at 3 gpm, how long will it take to fill?