The coefficient of thermal conductivity ...

The coefficient of thermal conductivity of copper is nine times that of steel. In the composite cylindrical bar shown in Fig. what will be the temperature at the junction of copper and steel ?

`75^@C`

`67^@C`

`33^@C`

`25^@C`

Text Solution

Verified by Experts

The correct Answer is:

`K_1=9K_2`,`l_1=18cm`,`l_2=6cm`,`theta_1=100^@C`,`theta_2=0^@C`
Temperature of the junction `theta=((K_1)/(l_1)theta_1+(K_2)/(l_2)theta_2)/((K_1)/(l_1)+(K_2)/(l_2))`
`impliestheta=((9K_2)/(18)100+(K_2)/(6)xx0)/((9K_2)/(18)+(K_2)/(6))=(50+0)/((8)/(12))=75^@C`

Topper's Solved these Questions

CALORIMETRY
CENGAGE PHYSICS ENGLISH|Exercise Multiple Correct|25 Videos
CALORIMETRY
CENGAGE PHYSICS ENGLISH|Exercise Comprehension|30 Videos
CALORIMETRY
CENGAGE PHYSICS ENGLISH|Exercise Subjective|25 Videos
BASIC MATHEMATICS
CENGAGE PHYSICS ENGLISH|Exercise Exercise 2.6|20 Videos
CENTRE OF MASS
CENGAGE PHYSICS ENGLISH|Exercise INTEGER_TYPE|1 Videos

Similar Questions

Explore conceptually related problems

There indectical thermal conductors are connected as shown in Fig. 7(CF).17. Considering no heat is lost due to radition, the temperature of the junction is

Three metal rods made of copper, aluminium and brass, each 20 cm long 4cm in diameter, are placed end to end with aluminium between the other two. The free ends of copper and brass are maintained at 100 and 0^(@)C respectively. Assume that the thermal conductivity of copper is twice that of aluminium and four times that of brass. The approximately equilibrium temperatures of the copper-aluminiu and aluminium-brass junctions are respectively.

A steel bar 10.0 cm long is welded end to end to a copper bar 20.0 cm long. Both bars are insulated perfectly on their sides . Each bar has a separate cross-section, 2.00 cm on a side . The free end of the steel bar is maintained at 100^(@)C by placing it in contact with steam and free end of the copper bar is maintained at 0^(@)C by placing it in contact with ice . find the temperature at the junction of the two bars and the total rate of heat flow . thermal conductivity of steel = 50.2 Wm^(-1)K^(-1) .thermal conductivity of copper =385 Wm^(-1)K^(-1) .

Figure shows a copper rod joined to a steel rod. The rods have equal length and and the equal cross sectional area. The free end of the copper rod is kept at 0^(@)C and that of the steel rod is kept at 100^(@)C . Find the temperature at the junction of the rods. conductivity of copper =390Wm^(-1)C^(-1) and that of steel =46Wm^(-1)C^(-1) .

A rigid bar of mass 15 kg is supported symmetrically by three wires, each of length 2 m. The wires at the endpoints are made of copper and the middle one is made of steel. If the tension in each wire is the same, then the diameter of copper wire to the diameter of steel wire is ["Given, "Y_("copper")=1.1xx10^(11)"N m"^(-1) and Y_("steel")=1.9xx10^(11)"N m"^(-2)]

Three rods of same dimensions have thermal conductivity 3K,2K and K They are arranged as shown in Then the temperature of the junction in steady state is .

Three rods of the same dimension have thermal conductivity 3K , 2K and K. They are arranged as shown in the figure below Then , the temperature of the junction in steady - state is

In an experiment to determine the thermal conductivity of copper with Searle's apparatus, 100 gm of water flowed in 4.2 minutes past the cold end of the copper bar, its initial and final temperatures being 25°C and 52°C respectively. If the temperature difference between two points in the bar 10 cm apart is 23°C and the area of cross-section of the bar is 5 "cm"^2 , calculate the coefficient of thermal conductivity of copper. Specific heat capacity of water 4,200 "J kg"^(-1) "K"^(-1)

Coefficient of thermal conductivity is the product of heat, distance and reciprocal of (area x difference in temperature x time). The new value of a unit of coefficient of thermal conductivity, if fundamental units are 21.6 kg, 1 decimetre, 4 K and 1 minute will be ______ xx 10^(-6) new units.

CENGAGE PHYSICS ENGLISH-CALORIMETRY-Single Correct

Two rods are of same material and having same length and area. If heat...
Text Solution
|
Three rods of same dimensions are arranged as shown in figure. They ha...
Text Solution
|
The coefficient of thermal conductivity of copper is nine times that o...
Text Solution
|
Six identical conducting rods are joined as shown figure. Points A and...
Text Solution
|
An ice box used for keeping eatables cool has a total wall area of 1m^...
Text Solution
|
The only possibility of heat flow in a thermos flask is through its co...
Text Solution
|
Certain substance emits only the wavelengths lamda1,lamda2,lamda3 and ...
Text Solution
|
Figure. Shows two air filled bulbs connected by a U-tube partly filled...
Text Solution
|
A black body at 200 K is found to emit maximum energy at a wavelength ...
Text Solution
|
A black body radiates poer P and maximum energy is radiated by it arou...
Text Solution
|
The wavelength of maximum energy released during an atomic axplosion w...
Text Solution
|
The rectangular surface of area 8 cm xx 4 cm of a black body at temper...
Text Solution
|
A solid copper cube of edges 1 cm is suspended in an evacuated enclosu...
Text Solution
|
A sphere, a cube and a thin circular pate are heated to the same tempe...
Text Solution
|
A sphere and a cube of same material and same volume are heated up to ...
Text Solution
|
A substance cools from 75^@C to 70^@C in T1 minute, from 70^@C to 65^@...
Text Solution
|
A liquid takes 5 minutes to cool from 80^@C to 50^@C . How much time w...
Text Solution
|
A body takes T minutes to cool from 62^@C to 61^@C when the surroundin...
Text Solution
|
The rates of cooling of two different liquids put in exactly similar c...
Text Solution
|
Hot water cools from 60^@C to 50^@C in the first 10 min and to 42^@C i...
Text Solution
|