Two spherical black bodies of radii ${r_1}$ and ${r_2}$ and with surface temperature ${T_1}$and ${T_2}$ respectively radiate the same power. Then the ratio of ${r_1}$ and ${r_2}$ will be
  • A${\left( {\frac{{{T_2}}}{{{T_1}}}} \right)^2}$
  • B${\left( {\frac{{{T_2}}}{{{T_1}}}} \right)^4}$
  • C${\left( {\frac{{{T_1}}}{{{T_2}}}} \right)^2}$
  • D${\left( {\frac{{{T_1}}}{{{T_2}}}} \right)^4}$
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