A solid cylinder of length $L$ and radius $r$ is heat upto same temperature as that of a cube of edge length $a$. If both have same material, volume and allowed to cool under similar conditions, then ratio of amount of radiations radiated will be (Neglect radiation emitted from flat surfaces of the cylinder)
  • A$\frac{a}{3 r}$
  • B$\frac{2 a}{r L}$
  • C$\frac{a^2}{r L}$
  • D$\frac{\pi a^2}{2 \pi L}$
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