Two different rods $A$ and $B$ are kept as shown in figure. The variation of temperature of different cross sections is plotted in a graph shown in figure. The ratio of thermal conductivities of $A$ and $B$ is
A$2$
B$0.5$
C$1$
D$2/3$
Medium
Download our app for free and get started
B$0.5$
b $\because\left(\frac{\Delta \mathrm{Q}}{\Delta \mathrm{t}}\right)_{\mathrm{A}}=\left(\frac{\Delta \mathrm{Q}}{\Delta \mathrm{t}}\right)_{\mathrm{B}} \quad \therefore \frac{\mathrm{K}_{\mathrm{A}} \mathrm{A}(100-70)}{30}$
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.*
If a liquid takes $30 \;sec$ in cooling from $80^{\circ} C$ to $70^{\circ} C$ and $70 \;sec$ in cooling from $60^{\circ} C$ to $50^{\circ} C$, then find the room temperature.
The temperature of a piece of iron is ${27^o}C$ and it is radiating energy at the rate of $Q\;kW{m^{ - 2}}$. If its temperature is raised to ${151^o}C$, the rate of radiation of energy will become approximately ....... $Q\,kW\,{m^{ - 2}}$
It is estimated that per minute each $cm^2$ of earth receives about $2\ cal (1\ cal = 4.18\ J)$ of heat energy from the sun. This is called Solar constant. In $SI$ units the value is
In an experment ot verify Newton's law of cooling, a graph is plotted between, the temperature difference $(\Delta T )$ of the water and surroundings and time as shown in figure. The initial temperature of water is taken as $80^{\circ} \,C$. The value of $t _{2}$ as mentioned in the graph will be...........
Parallel rays of light of intensity $I =912 \ Wm ^{-2}$ are incident on a spherical balck body kept in surroundings of temperature $300 \ K$. Take Stefan-Boltzmann constant $\sigma=5.7 \times 10^{-8} Wm ^{-2} K ^{-4}$ and assume that the energy exchange with the surroundings is only through radiation. Th final steady state temperature of the black body is close to:
Wein's constant is $2892 \times {10^{ - 6}}$$MKS$ unit and the value of ${\lambda _m}$ from moon is $14.46$ microns. What is the surface temperature of moon ...... $K$
The temperature gradient in a rod of $0.5 m$ long is ${80^o}C/m$. If the temperature of hotter end of the rod is ${30^o}C$, then the temperature of the cooler end is ...... $^oC$