Two rods of different material have same length and cross-section area. They take 20 min and 35 min respectively to melt same mass of ice under the condition that the ends of both are always at temperature 0°C and T°C. The ratio of thermal conductivites are :-

7:4

1:2

2:1

1:3

Two rectangular blocks A and B of different metals have same length and same area of cross-section. They are kept in such a way that their cross-sectional area touch each other. The temperature at one end of A is 100^(@)C and B at the other end is 0^(@)C . If the ratio of their thermal conductivity is 1 : 3 , then under steady state, the temperature of the junction in contact will be

Three rods made of the same material and having same cross-section area but different length 10 cm, 20 cm and 30 cm are joined as shown. The temperature of the junction is

Wires A and B have have identical lengths and have circular cross-sections. The radius of A is twice the radius of B i.e. R_A = 2R_B . For a given temperature difference between the two ends, both wires conduct heat at the same rate. The relation between the thermal conductivities is given by-

Three rods of material X and three rods of material Y are connected as shown in the figure. All the rods are of identical length and cross-sectional area. If the end A is maintained at 60^@C and the junction E at 10^@C . Calculate the temperature of the junction B, C and D. The thermal conductivity of X is 0.92cal//sec-cm^@C and that of Y is 0.46cal//sec-cm-^@C .

The length of the two rods made up of the same metal and having the same area of cross-section are 0.6 m and 0.8 m respectively. The temperature between the ends of first rod is 90^(@) C and 60^(@) C and that for the other rod is 150 and 110^(@) C. For which rod the rate of conduction will be greater

A semicircular rods is joined at its end to a straight rod of the same material and the same cross-sectional area. The straight rod forms a diameter of the other rod. The junctions are maintained at different temperatures. Find the ratio of the heat transferred through a cross section of the straight rod in a given time.

Two vessels of different materials are similar in size in every respect. The same quantity of ice filled in them gets melted in 20 minutes and 40 minutes respectively. The ratio of thermal conductivities of the metals is

Two vessels 1 and 2, made out of different materials are identical in all the geometrical aspects. In both the vessel the same quantity of ice gets melted in 20 min and 30 min respectively. The ratio of the thermal conductivity of the second one to that of the first is

Three rods are made from the same material and having the same cross-sectional area and length have been joined as shown in the figure. The left end and right end are kept 0^@C and 100^@C , respectively . The temperature of the junction of three rods will be

Three rods A, B and C of the same length and same cross-sectional area are joined as shown. Their thermal conductivities are in the ratio 1:2:3/2. If the open ends of A and C are at 200^@ C and 18^@ C, respectively, then the temperature at the junction of A at steady state is