A black body at $227^o C$ radiates heat at the rate of $7\; cals/cm^2 s$. At a temperature of $727^o C$, the rate of heat radiated in the same units will be 
  • A$50$
  • B$112$
  • C$80$
  • D$60$
AIPMT 2009, Medium
art

Download our app
and 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

  • 1
    Spheres $P$ and $Q$ are uniformly constructed from the same material which is a good conductor of heat and the radius of $Q$ is thrice the radius of $P$. The rate of fall of temperature of $P$ is $x$ times that of $Q$ when both are at the same surface temperature. The value of $x$ is :
    View Solution
  • 2
    The thickness of a metallic plate is $0.4 cm$ . The temperature between its two surfaces is ${20^o}C$. The quantity of heat flowing per second is $50$ calories from $5c{m^2}$ area. In $CGS$ system, the coefficient of thermal conductivity will be
    View Solution
  • 3
    Two different rods $A$ and $B$ are kept as shown in figure. The ratio of thermal conductivities of $A$ and $B$ is
    View Solution
  • 4
    A spherical black body with a radius of $12\ cm$ radiates $450\ watt$ power at $500\ K$. If the radius were halved and the temperature doubled, the power radiated in watt would be
    View Solution
  • 5
    A black body at $200 K$ is found to exit maximum energy at a wavelength of $14\mu m$. When its temperature is raised to $1000K$ , the wavelength at which maximum energy is emitted is
    View Solution
  • 6
    Two thin metallic spherical shells of radii ${r}_{1}$ and ${r}_{2}$ $\left({r}_{1}<{r}_{2}\right)$ are placed with their centres coinciding. A material of thermal conductivity ${K}$ is filled in the space between the shells. The inner shell is maintained at temperature $\theta_{1}$ and the outer shell at temperature $\theta_{2}\left(\theta_{1}<\theta_{2}\right)$. The rate at which heat flows radially through the material is :-
    View Solution
  • 7
    The ends of two rods of different materials with their thermal conductivities, radii of cross-sections and lengths all are in the ratio $1:2$ are maintained at the same temperature difference. If the rate of flow of heat in the larger rod is $4\;cal/\sec $, that in the shorter rod in $cal/\sec $ will be
    View Solution
  • 8
    Four rods of same material and having the same cross section and length have been joined, as shown. The temperature of the junction of four rods will be ............... $^{\circ} C$
    View Solution
  • 9
    The coefficient of thermal conductivity depends upon
    View Solution
  • 10
    Instantaneous temperature difference between cooling body and the surroundings obeying Newton's law of cooling is $\theta$. Which of the following represents the variation of $\ln \theta$ with time $t$ ?
    View Solution