A room has a `4mxx4mxx10cm` concrete roof `(K=1.26Wm^(-1)`^(@)C^(-1)` . At some instant, the temperature outside is `40(@)C` and that inside is 32(@)C` . (a) Neglecting converction, calculate the amount of heat flowing per second into the room through the roof. (b) Bricks `(K=0.65Wm^(-1)`^(@)C^(-1) of thickness `7.5cm` are loid down on the roof. Calculate the new rate of heat flow under the some temperature conditions.

A room has a 4mxx4mxx10cm concrete roof (K=1.26Wm^(-1)C^(-1)) . At some instant, the temperature outside is 46^(@)C and that inside is 32^(@)C . (a) Neglecting convection, calculate the amount of heat flowing per second into the room through the roof. (b) Bricks (K=0.65Wm^(-1)C^(-1)) of thickness 7.5cm are laid down on the roof. Calculate the new rate of heat flow under the some temperature conditions.

The area of a glass window is 1.2 m^(2) . The thickness of the glass is 2.2 mm. If the temperature outside is 36°C and the temperature inside is 26°, calculate the heat flowing into the room every hour. Thermal conductivity of glass is 0.8 Wm^(-1) K^(-1) .

A room has a window fixed with a pane of area 1.2m^(s) The glass has thickness 2.2mm If the temperature outside the room is 36^(@)C and the temperature inside is 26^(@)C (a) calculate the heat flowing into the room every hour (b) If the same single pane window is replaced by double paned window with an air gap of 0.50cm between the two panes calculate the heat flowing into the room every hour K_(g) =0.80 Wm^(-1)K^(-1),K_(air)=0.0234Wm^(-1)K^(-1) .

One face of a copper cube of edge 10 cm is maintained at 100^(@)C and the opposite face is maintained at 0^(@)C . All other surfaces are covered with an insulating material. Find the amount of heat flowing per second through the cube. Thermal conductivety of copper is 385Wm^(-1) ^(@)C^(-1) .

A room has s window fitted with a single 1.0mxx2.0m glass of thickness 2mm. (a) Calculate the rate of heat flow through the closed window when the temperature inside the room is 32^(@)C and that outside is 40^(@)C . (b) The glass is now replaced by two glasspanes, each having a thickness of 1mm and separated by a distance of 1mm. Calculate the rate of heat flow under the same condition of temperature. Thermal conductivity of window glass =1.0Js^(-1)m^(-1)C^(-1) and that of air =0.025Js^(-1)m^(-1)C^(-1) .

A room has s window fitted with a single 0.1mxx2.0m glass of thickness 2mm. (a) Calculate the rate of heat flow through the clossed window when the temperature inside the room is 32^(@)C and that outside is 40^(@)C . (b) The glass is now replaced by two glasspance, each having a thickness of 1mm and separated by a distance of 1mm. Calculalte the rate of heat flow under the same condition of temperature. Thermal conductivity of window glass =1.0Js^(-1)m^(-1) ^(@)C^(-1) and that of air =0.025Js^(-1)m^(-1) ^(@)C^(-1) .

One face of a copper cube of edge 10 cm is maintained at 100^(@)C and the opposite face is maintained at 0^(@)C . All other surfaces are covered with an insulating material. Find the amount of heat flowing per second through the cube. Thermal conductivity of copper is 385Wm^(-1) C^(-1) .

One face of a copper cube of edge 10 cm is maintained at 100^(@)C and the opposite face is maintained at 0^(@)C . All other surfaces are covered with an insulating material. Find the amount of heat flowing per second through the cube. Thermal conductivity of copper is 385Wm^(-1) C^(-1) .

A metal rod of cross sectional area 1.0cm^(2) is being heated at one end. At one time , the temperature gradient is 5.0^(@)C cm^(-1) at cross section A and is 2.5^(@)Ccm^(-1) at cross section B. calculate the rate at which the temperature is increasing in the part AB of the rod. The heat capacity of the part AB =0.40J^(@)C^(-1) , thermal conductivity of the material of the rod. K=200Wm^(-1)C^(-1) . Neglect any loss of heat to the atmosphere.

A metal rod of cross sectional area 1.0cm^(2) is being heated at one end. At one time , the temperature gradient is 5.0^(@)C cm^(-1) at cross section A and is 2.5^(@)Ccm^(-1) at cross section B. calculate the rate at which the temperature is increasing in the part AB of the rod. The heat capacity of the part AB =0.40J^(@)C^(-1) , thermal conductivity of the material of the rod. K=200Wm^(-1)C^(-1) . Neglect any loss of heat to the atmosphere.