Thermal Propert...

Four identical rods of same material are joined at ends so as to form a square. If the temperature difference at the ends of a diagonal is 100$$^{o}$$C, then the temperature difference across the ends of another diagonal will be

A double-pane window used for insulating a room thermally from outside consists of two glass sheets each of area 1m$$^{2}$$ and thickness $$0.01$$m separated by $$0.05$$m thick stagnant air space.In the steady state, the room-glass interface and the glass-outdoor interface are at constant temperatures of 27$$^{o}$$C and 0$$^{o}$$C respectively.The thermal conductivity of glass is $$0.8$$ and of air 0.08Wm$$^{-1}$$K$$^{-1}$$

The temperature of the outer glass-air interface is

A double-pane window used for insulating a room thermally from outside consists of two glass sheets each of area 1m$$^{2}$$ and thickness 0.01m separated by 0.05m thick stagnant air space.In the steady state, the room-glass interface and the glass-outdoor interface are at constanttemperatures of 27$$^{o}$$C and 0$$^{o}$$C respectively.The thermal conductivity of glass is 0.8 and of air 0.08Wm$$^{-1}$$K$$^{-1}$$

The temperatures of the inner glass-air interface is

Three rods A,B and C have the same dimensions.Their conductivities are $$K_{A}, K_{B}$$  and $$ K_{C}$$ respectively. A and B are placed end to end, with their free ends kept at certain temperature difference. C is placed separately with its ends kept at same temperature difference. The two arrangements conduct heat at the same rate $$K_{c}$$ must be equal to

A vessel contains air and saturated vapor. The pressure of air is $$\mathrm{p}_{2}$$ and $$\mathrm{p}_{1}$$ is the S.V. P. On compressing the mixture to one-fourth of its original volume, what is the increase in pressure of the mixture?

An electric kettle takes 4 A current at 220 V.
How much time will it take to boil 1 kg of water
from temperature
$$ 20^{0}C ?$$  The temperature of
boiling water is
$$ 100^{0}C ?$$

Consider two rods of same length and different specific heats (S$$_{1}$$, S$$_{2}$$), conductivity (K$$_{1}$$, K$$_{2}$$) and area of cross-sections (A$$_{1}$$, A$$_{2}$$) and both having temperature T$$_{1}$$ and T$$_{2}$$ at their ends. If rate of loss of heat due to conduction is equal, then:

Two plates of same area are placed in contact. Their thickness as well as thermal conductivities are in the ratio 2 : 3. The outer surface of one plate is maintained at $$10^\circ C$$ and that of other at $$0^\circ C$$. What is the temp.of the common surface?

A cylinder of radius r and thermal conductivity $$K_1$$ is surrounded by a cylindrical shell of inner radius r and outer radius 2 r, whose thermal conductivity is $$K_2$$. There is no loss of heat across cylindrical surfaces, when the ends of the combined system are maintained at temps. $$T_1$$  and  $$T_2$$. The effective thermal conductivity of the system, in the steady state is