Energy is being emitted from the surface of a black body at $127\,^oC$ temperature at the rate of $1.0 \times {10^6}\,J/s - {m^2}$. Temperature of the black body at which the rate of energy emission is $16.0 \times {10^6}\,J/s - {m^2}$ will be   ......... $^oC$
Medium
Download our app for free and get startedPlay store
$T_{1}=127^{\circ} C=400 K$

$E_{2}=16 \times 10^{6} J / s m^{2}$

$E_{1}=1 \times 10^{6} J / \mathrm{sm}^{2}$

Using the relation.

$\frac{E_{2}}{E_{1}}=\left(\frac{T_{2}}{T_{1}}\right)^{4}$

$\frac{T_{2}}{T_{1}}=\frac{E_{2}}{E_{1}}=\left(\frac{16.0 \times 10^{6}}{1 \times 10^{6}}\right)^{1 / 4}=2$

$T_{2}=2 \times T_{1}=2 \times 400=800 K$

$T_{2}=527^{\circ} \mathrm{C}$

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
    The spectrum from a black body radiation is a
    View Solution
  • 2
    $A$ wall has two layers $A$ and $B$ made of different materials. The thickness of both the layers is the same. The thermal conductivity of $A$ and $B$ are $K_A$ and $K_B$ such that $K_A = 3K_B$. The temperature across the wall is $20°C$ . In thermal equilibrium
    View Solution
  • 3
    A body cools in a surrounding which is at a constant temperature of ${\theta _0}$. Assume that it obeys Newton's law of cooling. Its temperature $\theta $ is plotted against time $t$ . Tangents are drawn to the curve at the points $P(\theta = {\theta _1})$ and $Q(\theta = {\theta _2})$. These tangents meet the time axis at angles of ${\varphi _2}$and ${\varphi _1}$, as shown
    View Solution
  • 4
    There is formation of layer of snow $x\,cm$ thick on water, when the temperature of air is $ - {\theta ^o}C$ (less than freezing point). The thickness of layer increases from $x$ to $y$ in the time $t$, then the value of $t$is given by
    View Solution
  • 5
    A sphere of density $\rho $ , specific heat capacity $c$ and radius $r$ is hung by a thermally insulating thread in an enclosure which is kept at a lower temperature than the sphere. The temperature of the sphere starts to drop at a rate which depends upon the temperature difference between the sphere and the enclosure and the nature of the surface of sphere and is proportional to
    View Solution
  • 6
    A constant potential difference is applied to the ends of a graphite rod, whose resistance decreases with a rise of temperature. The rod can be $(1)$ covered with asbestos or $(2)$ left open to atmosphere. Answer for steady state.
    View Solution
  • 7
    The three rods shown in figure have identical dimensions. Heat flows from the hot end at a rate of $40 \,W$ in the arrangement $(a)$. Find the rates of heat flow when the rods are joined as in arrangement $(b)$ is ......... $W$ (Assume $K_al=200 \,W / m ^{\circ} C$ and $\left.K_{c u}=400 \,W / m ^{\circ} C \right)$
    View Solution
  • 8
    The Wien’s displacement law express relation between
    View Solution
  • 9
    A body initially at $80^o C$ cools to $64^o C$ in $5$ minutes and to $52^o C$ in $10 $ minutes. The temperature of the body after $15$ minutes will be ...... $^oC$
    View Solution
  • 10
    The wavelength of radiation emitted by a body depends upon
    View Solution