Three rods of the same dimension have thermal conductivities $3K$ , $2K$ and $K$ . They are arranged as shown in fig. Given below, with their ends at $100^oC, 50^oC $and $20^oC$. The temperature of their junction is ......... $^oC$
Medium
Download our appand get started for free
Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*
Similar Questions
- 1The coefficient of thermal conductivity of copper is nine 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 ....... $^oC$View Solution
- 2Two spheres of same material have radius $1m$ and $4 m$ and temperature $4000K$ and $2000K$ respectively. The energy radiated per second by the first sphere isView Solution
- 3Steel wire of length ' $L$ ' at $40^{\circ} C$ is suspended from the ceiling and then a mass ' $m$ ' is hung from its free end. The wire is cooled down from $40^{\circ} C$ to $30^{\circ} C$ to regain its original length ' $L$ '. The coefficient of linear thermal expansion of the steel is $10^{-5} /{ }^{\circ} C$, Young's modulus of steel is $10^{11} N / m ^2$ and radius of the wire is $1 \ mm$. Assume that $L \gg$ diameter of the wire. Then the value of ' $m$ ' in $kg$ is nearlyView Solution
- 4View SolutionMud houses are cooler in summer and warmer in winter because
- 5Match the temperature of a black body given in List-$I$ with an appropriate statement in List-$II$, and choose the correct option.View Solution
[Given: Wien's constant as $2.9 \times 10^{-3} \mathrm{~m}-\mathrm{K}$ and $\frac{\mathrm{hc}}{\mathrm{e}}=1.24 \times 10^{-6} \mathrm{~V}-\mathrm{m}$ ]
List-$I$ List-$II$ ($P$) $2000 \mathrm{~K}$ ($1$) The radiation at peak wavelength can lead to emission of photoelectrons from a metal of work function $4 \mathrm{eV}$ ($Q$) $3000 \mathrm{~K}$ ($2$) The radiation at peak wavelength is visible to human eye. ($R$) $5000 \mathrm{~K}$ ($3$) The radiation at peak emission wavelength will result in the widest central maximum of a single slit diffraction. ($S$) $10000 \mathrm{~K}$ ($4$) The power emitted per unit area is $1 / 16$ of that emitted by a blackbody at temperature $6000 \mathrm{~K}$. ($5$) The radiation at peak emission wavelength can be used to image human bones. - 6The top of insulated cylindrical container is covered by a disc having emissivity $0.6$ and thickness $1\, cm$. The temperature is maintained by circulating oil as shown in figure. If temperature of upper surface of disc is $127^o C$ and temperature of surrounding is $27^o C$, then the radiation loss to the surroundings will be (Take $\sigma = \frac{{17}}{3} \times {10^{ - 8}}W/{m^2}{K^4})$View Solution
- 7$Assertion :$ For higher temperature the peak emission wavelength of a blackbody shifts to lower wavelengths.View Solution
$Reason :$ Peak emission wavelengths of a black body is proportional to the fourth-power of temperature.
- 8The radiation emitted by a star $A$ is $10,000$ times that of the sun. If the surface temperatures of the sun and the star $A$ are $6000 K$ and $2000 K$ respectively, the ratio of the radii of the star $A$ and the sun isView Solution
- 9View SolutionIce formed over lakes has
- 10View SolutionThe spectral energy distribution of star is maximum at twice temperature as that of sun. The total energy radiated by star is