Question:
The coefficient of thermal conductivity of copper is $9$ times that of steel. In the composite cylindrical bar shown in the figure, what will be the temperature at the junction of copper and steel ?
The coefficient of thermal conductivity of copper is $9$ times that of steel. In the composite cylindrical bar shown in the figure, what will be the temperature at the junction of copper and steel ?
Updated On: Feb 23, 2024
- 75$^\circ$C
- 67 $^\circ$C
- 25 $^\circ$C
- 33$^\circ$C
Hide Solution
Verified By Collegedunia
The Correct Option is A
Solution and Explanation
Temperature of interface
$\theta=\frac{K_{1} \theta_{1} l_{2}+K_{2} \theta_{2} l_{1}}{K_{1} l_{2}+K_{2} l_{1}}$
It is given that $K_{ Cu }=9 K_{s} .$ So, if $K_{s}=K_{1}=K$, then
$K_{ Cu }=K_{2} =9\, K $
$\Rightarrow \,\,\,\theta =\frac{9 K \times 100 \times 6+K \times 0 \times 18}{9 K \times 6+K \times 18} $
$=\frac{5400 K }{72 K }=75^{\circ} \,C$
$\theta=\frac{K_{1} \theta_{1} l_{2}+K_{2} \theta_{2} l_{1}}{K_{1} l_{2}+K_{2} l_{1}}$
It is given that $K_{ Cu }=9 K_{s} .$ So, if $K_{s}=K_{1}=K$, then
$K_{ Cu }=K_{2} =9\, K $
$\Rightarrow \,\,\,\theta =\frac{9 K \times 100 \times 6+K \times 0 \times 18}{9 K \times 6+K \times 18} $
$=\frac{5400 K }{72 K }=75^{\circ} \,C$
Was this answer helpful?
0
0
Top Questions on Heat Transfer
- In the steady state of temperature, the flow of heat across the body depends upon its:
A. thermal capacity
B. thermal conductivity
C. temperature difference across its opposite faces
D. thermal resistivity
Choose the CORRECT answer from the options given below:- CUET (PG) - 2025
- Physics
- Heat Transfer
Match the LIST-I with LIST-II
LIST-I LIST-II (Type of Fouling) (Fouling Mechanism) A Precipitation IV Precipitation of dissolved substances... B Freezing III Solidification of Liquid components... C Particulate I Accumulation of fine particles suspended... D Corrosion II Heat transfer surface reacts with ambient... Identify the evaporator
- The difference between the initial and the final temperature divided by the freezing time is known as
- The Nusselt number is related to the Reynolds number in laminar and turbulent flows respectively as:
- CUET (PG) - 2025
- Mechanical Engineering
- Heat Transfer
View More Questions
Questions Asked in KCET exam
Match the following:
In the following, \( [x] \) denotes the greatest integer less than or equal to \( x \).
Choose the correct answer from the options given below:- KCET - 2025
- Differentiability
- If \[ y = \frac{\cos x}{1 + \sin x} \] then:
- KCET - 2025
- Differentiability
- A function \( f(x) \) is given by:
\[ f(x) = \begin{cases} \frac{1}{e^x - 1}, & \text{if } x \neq 0 \\ \frac{1}{e^x + 1}, & \text{if } x = 0 \end{cases} \] Then, which of the following is true?- KCET - 2025
- Limits
- The function f(x) is given by:
For x < 0:
f(x) = ex + axFor x ≥ 0:
f(x) = b(x - 1)2
The function is differentiable at x = 0. Then,- KCET - 2025
- Differentiability
- The function \( f(x) = \tan x - x \)
- KCET - 2025
- Derivatives
View More Questions
Concepts Used:
Heat Transfer
What is Heat Transfer?
It is defined as the movement of heat across the border of the system due to a difference in temperature between system and its surroundings.
How is Heat Transferred?
Heat can travel from one place to another in several ways. The different modes of heat transfer include:
- Conduction - Heat flows from things with higher temp to objects with lower temp.
- Convection - Movement of liquid molecules from higher temp regions to lower temp regions.
- Radiation - Radiant heat is present in every other way in our daily lives. Thermal radiations are also known to as radiant heat. Thermal radiation is generated by the emission of electromagnetic waves.
