What will be the ratio of temperatures of sun and moon if the wavelengths of their maximum emission radiations rates are $140 Å$ and $4200 Å$ respectively
  • A$1:30$
  • B$30:1$
  • C$42:14$
  • D$14:42$
Easy
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 value of Stefan’s constant is
    View Solution
  • 2
    The following three objects $(1)$ a metal tray, $(2)$ a block of wood and $(3)$ a woolen cap are left in a closed room overnight. Next day, the temperature of each is recorded as $T_1, T_2$ and $T_3$, respectively. The likely situation is
    View Solution
  • 3
    In which case the thermal conductivity increases from left to right
    View Solution
  • 4
    A solid copper sphere (density $\rho $ and specific heat capacity $c$ ) of radius $r$ at an initial temperature $200K$ is suspended inside a chamber whose walls are at almost $0K$ . The time required (in $\mu s$) for the temperature of the sphere to drop to $100\, K$  is
    View Solution
  • 5
    Pick out the statement which is not true
    View Solution
  • 6
    Two spheres of the same material have radii $1\; m$ and $4\; m$ and temperatures $4000 \;K$ and $2000 \;K$ respectively. The ratio of the energy radiated per second by the first sphere to that by the second is
    View Solution
  • 7
    A slab consists of two parallel layers of copper and brass of the same thickness and having thermal conductivities in the ratio $1 : 4$ . If the free face of brass is at ${100^o}C$ and that of copper at $0^\circ C $, the temperature of interface is ........ $^oC$
    View Solution
  • 8
    $Assertion :$ A hollow metallic closed container maintained at a uniform temperature can act as a source of black body radiation.
    $Reason :$ All metals act as black bodies.
    View Solution
  • 9
    Newton's law of cooling is a special case of
    View Solution
  • 10
    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