00. Conduction
Heat Transfer

149327 The temperature of the two outer surfaces of a composite slab, consisting of two materials having coefficients of thermal conductivity K and 2K and thickness x and 4x, respectively are T2 and T1(T2>T1). The rate of heat transfer through the slab, in a steady state is
(A(T2T1)Kx)f, with f equals to 
C1T1

1 1
2 1/2
3 2/3
4 1/3
Heat Transfer

149328 Cylindrical rod of copper of length 2 m and cross-sectional area 2cm2 is insulated at its curved surface. The one end of rod is maintained in steam chamber and other is maintained in ice at 0C. The thermal conductivity of copper is 386Js1 m1C1 ). Fin the temperature at a point which is at a distance of 120 cm from the colder end.

1 80C
2 50C
3 60C
4 70C
Heat Transfer

149330 A composite bar of uniform cross-section is made of 25 cm of copper, 10 cm of nickel and 15 cm of aluminum with perfect thermal contacts. The free copper end of the rod is at 100C and the free aluminum end is at 0C. If KCu=2 KAl and KAl=3 KNi then the temperatures of CuNi and NiAl junctions are respectively,
(Assume no loss of heat occurs from the sides of the rod, K-thermal conductivity),

1 82.3C,31.3C
2 78.3C,26.1C
3 70C,23.3C
4 90.3C,30.1C
Heat Transfer

149327 The temperature of the two outer surfaces of a composite slab, consisting of two materials having coefficients of thermal conductivity K and 2K and thickness x and 4x, respectively are T2 and T1(T2>T1). The rate of heat transfer through the slab, in a steady state is
(A(T2T1)Kx)f, with f equals to 
C1T1

1 1
2 1/2
3 2/3
4 1/3
Heat Transfer

149328 Cylindrical rod of copper of length 2 m and cross-sectional area 2cm2 is insulated at its curved surface. The one end of rod is maintained in steam chamber and other is maintained in ice at 0C. The thermal conductivity of copper is 386Js1 m1C1 ). Fin the temperature at a point which is at a distance of 120 cm from the colder end.

1 80C
2 50C
3 60C
4 70C
Heat Transfer

149329 Three rods each of length l and cross sectional area A joined in series between two heat reservoirs as shown in the figure. Their conductivities are 2 K, K and K2, respectively.
Assuming that the conductors are insulated from surroundings, the temperatures T1 and T2 of the junctions in steady state condition are respectively.

1 6007C,4007C
2 6007C,7004C
3 5006C,6005C
4 6004C,4007C
Heat Transfer

149330 A composite bar of uniform cross-section is made of 25 cm of copper, 10 cm of nickel and 15 cm of aluminum with perfect thermal contacts. The free copper end of the rod is at 100C and the free aluminum end is at 0C. If KCu=2 KAl and KAl=3 KNi then the temperatures of CuNi and NiAl junctions are respectively,
(Assume no loss of heat occurs from the sides of the rod, K-thermal conductivity),

1 82.3C,31.3C
2 78.3C,26.1C
3 70C,23.3C
4 90.3C,30.1C
Heat Transfer

149327 The temperature of the two outer surfaces of a composite slab, consisting of two materials having coefficients of thermal conductivity K and 2K and thickness x and 4x, respectively are T2 and T1(T2>T1). The rate of heat transfer through the slab, in a steady state is
(A(T2T1)Kx)f, with f equals to 
C1T1

1 1
2 1/2
3 2/3
4 1/3
Heat Transfer

149328 Cylindrical rod of copper of length 2 m and cross-sectional area 2cm2 is insulated at its curved surface. The one end of rod is maintained in steam chamber and other is maintained in ice at 0C. The thermal conductivity of copper is 386Js1 m1C1 ). Fin the temperature at a point which is at a distance of 120 cm from the colder end.

1 80C
2 50C
3 60C
4 70C
Heat Transfer

149329 Three rods each of length l and cross sectional area A joined in series between two heat reservoirs as shown in the figure. Their conductivities are 2 K, K and K2, respectively.
Assuming that the conductors are insulated from surroundings, the temperatures T1 and T2 of the junctions in steady state condition are respectively.

1 6007C,4007C
2 6007C,7004C
3 5006C,6005C
4 6004C,4007C
Heat Transfer

149330 A composite bar of uniform cross-section is made of 25 cm of copper, 10 cm of nickel and 15 cm of aluminum with perfect thermal contacts. The free copper end of the rod is at 100C and the free aluminum end is at 0C. If KCu=2 KAl and KAl=3 KNi then the temperatures of CuNi and NiAl junctions are respectively,
(Assume no loss of heat occurs from the sides of the rod, K-thermal conductivity),

1 82.3C,31.3C
2 78.3C,26.1C
3 70C,23.3C
4 90.3C,30.1C
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Heat Transfer

149327 The temperature of the two outer surfaces of a composite slab, consisting of two materials having coefficients of thermal conductivity K and 2K and thickness x and 4x, respectively are T2 and T1(T2>T1). The rate of heat transfer through the slab, in a steady state is
(A(T2T1)Kx)f, with f equals to 
C1T1

1 1
2 1/2
3 2/3
4 1/3
Heat Transfer

149328 Cylindrical rod of copper of length 2 m and cross-sectional area 2cm2 is insulated at its curved surface. The one end of rod is maintained in steam chamber and other is maintained in ice at 0C. The thermal conductivity of copper is 386Js1 m1C1 ). Fin the temperature at a point which is at a distance of 120 cm from the colder end.

1 80C
2 50C
3 60C
4 70C
Heat Transfer

149329 Three rods each of length l and cross sectional area A joined in series between two heat reservoirs as shown in the figure. Their conductivities are 2 K, K and K2, respectively.
Assuming that the conductors are insulated from surroundings, the temperatures T1 and T2 of the junctions in steady state condition are respectively.

1 6007C,4007C
2 6007C,7004C
3 5006C,6005C
4 6004C,4007C
Heat Transfer

149330 A composite bar of uniform cross-section is made of 25 cm of copper, 10 cm of nickel and 15 cm of aluminum with perfect thermal contacts. The free copper end of the rod is at 100C and the free aluminum end is at 0C. If KCu=2 KAl and KAl=3 KNi then the temperatures of CuNi and NiAl junctions are respectively,
(Assume no loss of heat occurs from the sides of the rod, K-thermal conductivity),

1 82.3C,31.3C
2 78.3C,26.1C
3 70C,23.3C
4 90.3C,30.1C