Two rectangular blocks A and B of different metals have same leng… - Vidyadip

MCQ

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 that of $B$ 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 ........ $^oC$

✓
$25$
B
$50$
C
$75$
D
$100$

✓

Answer

Correct option: A.

$25$

a
(a) It is given that $\frac{{{K_1}}}{{{K_2}}} = \frac{1}{3}$ ==> ${K_1} = K$ then ${K_2} = 3K$
the temperature of the junction in contact
$\theta = \frac{{{K_1}{\theta _1} + {K_2}{\theta _2}}}{{{K_1} + {K_2}}}$$ = \frac{{1 \times 100 + 3 \times 0}}{{1 + 3}} = \frac{{100}}{4}$= $25°C$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

JEE STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

A projectile is thrown with velocity $v$ at an angle $\theta$ with horizontal. When the projectile is at a height equal to half of the maximum height, the vertical component of the velocity of projectile is ...........

A body thrown vertically up with initial velocity $52 \,m / s$ from the ground passes twice a point at $h$ height above at an interval of $10 \,s$. The height $h$ is .........$m$ $\left(g=10 \,m / s ^2\right)$

The charge deposited on $4\,\mu F$ capacitor in the circuit is

The particle displacement of a travelling longitudional wave is represented by $\xi = \xi (x,t)$. The midpoints of a compression zone and an adjacent rarefaction zone are represented by the letter ‘$C’$ and $‘R’$. Which of the following is true?

The frequency of fundamental tone in an open organ pipe of length $0.48 m$ is $320 Hz.$ Speed of sound is $320 m/sec.$ Frequency of fundamental tone in closed organ pipe will be ... $Hz$

If two vectors $2\hat i + 3\hat j - \hat k$ and $ - 4\hat i - 6\hat j + \lambda \hat k$ are parallel to each other then value of $\lambda$ be

Under the same load, wire $A$ having length $5.0\,m$ and cross section $2.5 \times 10^{-5}\,m ^2$ stretches uniformly by the same amount as another wire $B$ of length $6.0\,m$ and a cross section of $3.0 \times 10^{-5}\,m ^2$ stretches. The ratio of the Young's modulus of wire $A$ to that of wire $B$ will be

A body of mass $m_1$ exerts a force on another body of mass $m_2$. If the magnitude of acceleration of $m_2$ is $a_2$, then the magnitude of the acceleration of $m_1$ is (considering only two bodies in space)

Two waves are approaching each other with a velocity of $16 m/s$ and frequency $n.$ The distance between two consecutive nodes is

An alpha nucleus of energy $\frac{1}{2}m{v^2}$ bombards a heavy nuclear target of charge $Ze$. Then the distance of closest approach for the alpha nucleus will be proportional to