The door of a refrigerator is 150 cm. high, 80 cm wide and 6 cm thick. If the coefficient of thermal conductivity is `5 xx 10^-4` `cal//cm`. s.`^@C` and the inner and outer surfaces are at `0^@C` and `30^@C` respectively. Calculate heat loss through the door in 1 minute.

A refrigerator door is 150 cm high, 80 cm wide and 6 cm thick. If the coefficient of conductiviy is 0.0005 (cal)/(cm s^@C) and the inner and outer surfaces are at O^@C and 30^@C respectively, then what is the heat loss (in calories) per minute through the door?

A wall of a room has dimensions of 6m xx 4m . It is 60 cm thick. Its thermal conductivity is is 2. If the temperature inside and outside is 20^@C and -5^@C respectively the amount of heat conducted every hour is about

A metal rod of diameter 1 cm measures 50 cm in length at 65 °C. If the coefficient of linear expansion of the rod is 16 x 10-6/ °C, the length of the rod at 0 °C will be

Water rises to a height of 10 cm in a capillary tube and mercury falls to a depth of 3.42 cm in the same capillary tube. If the density of mercury is 13.6 g//c.c. and the angles of contact for mercury and for water are 135^@ and 0^@ , respectively, the ratio of surface tension for water and mercury is

A charge of + 7 mu C is placed at the centre of two concentric spheres with radius 2.0 cm and 4.0 cm respectively. The ratio of the flux through them will be.

Three rods of copper, brass and steel are welded together to form a Y-shaped structure. Area of cross-section of each rod =4cm^2 . End of copper rod is maintained at 100^@C whereas ends of brass and steel are kept at O^@C . Lengths of the copper, brass and steel rods are 46, 13 and 12 cm respectively. The rods are thermally insulated from surroundings except at ends. Thermal conductivities of copper, brass and steel are 0.92, 0.26 and 0.12 CGS units respectively. Rate of heat flow through copper rod is

The specific conductance of 0.036 M KBr solution is 5.40 xx 10^(-4) S cm^(-1) . Find the molar conductivity of the solution.

When holes are dug into the Earth, it is found that for a depth of every 30 m, the temperature rises by 1^@C . If the coefficient of conductivity of Earth's crust is 0.8 watt//m^@k , calculate the amount of heat flowing through an area of 1 sq. metre on surface of earth, per minute

The molar conductivities ^^_(NaOAc)^(@) and ^^_(HCl)^(@) at infinite dilution in water at 25^(@)C are 91.0 and 426.2 S cm^(2)// mol respectively . To calculate ^^_(HOAc)^(@) , the additional value required is __________.

The conductivity of 0.02M AgN03 at 25^@C is 2.428 xx 10^(-3)Omega^(-1) cm^(-1) . What is its molar conductivity?