Thermal Propert...

If two conducting slabs of thickness $$d_1$$ and $$d_2$$, and thermal conductivity $$K_1$$ and $$K_2$$ are placed together face to face as shown in figure in the steady state temperatures of outer surfaces are $$O_1$$, and $$O_2$$. The temperature of common surface is 

If T represents the absolute temperature of an ideal gas, the volume coefficient of thermal expansion at constant pressure is proportional to:

Two models of a windowpane are made. In one model, two identical glass panes of thickness 3 mm are separated with an air gap of 3 mm. This composite system is fixed in the window of a room. The other model consists of a single glass pane of thickness 6 mm, the temperature difference being the same as for the first model. The ratio of the heat flow for the double pane  to that for the single pane is ($$K_{glass}\, =\, 2.5\, \times\, 10^{- 4}$$ cal / m. $$^{\circ}C$$ and $$K_{air}\, =\, 6.2\, \times\, 10^{- 6}$$ cal/s.m. $$^{\circ} C$$)

Three copper rods and three steel rods each of length $$l$$ = 10 cm and area of cross - section $$1\, cm^2$$ are connected as shown If ends A and E are maintained at temperatures $$125^{\circ}$$C and $$o^{\circ}$$C respectively, calculate the amount of heat flowing per second from the hot to cold function. $$[K_{cu}\, =\, 400\, W/m-K,\, K_{steel}\, =\, 50\, W/m-K]$$

A manufacture marks the thermometer wrongly. At 0$$^o$$ C it reads -10$$^o$$ C, at 100$$^o$$ C it reads 85$$^o$$C. Then the reading at 50$$^o$$ C will be :

A brass boiler has a base area of $$0.15 m^2$$ and thickness 1.0 cm. It boils water at the rate of 6.0 kg/min when placed on a gas stove. The temperature (approximately) of the part of the flame in contact with the boiler is (Thermal conductivity of brass $$= 107.4Js^{-1}m^{-1} {\;} ^oC^{-1}$$, Heat of vaporization of water $$= 2256\times 10^3J kg^{-1})$$.

Absolute zero corresponds to :

Which of the following curve represent variation of density of water with temperature best :   

A thermometer uses 'density of water' as thermometric property. The actual reading in the thermometer is 'height of water' (h) which is inversely proportional to density of water (d). In a certain temperature range, density of water varies with temperature as shown. The graph is symmetric about the maximum
Two identical bodies ( of same mass and specific heat ) at different temperatures $$T_1\, and\, T_2$$ show the same reading of height $$h_1\, =\,h_2$$ the thermometer. The bodies are brought into contact and allowed to reach thermal equilibrium. The thermometer reading 'height of water for final equilibrium state $$h_1$$ satisfies.

The boiling point of mercury is 367$$^o$$C. A mercury thermometer can be used to measure a temperature of 500$$^o$$C;