A sphere at temperature $600\,K$ is placed in an environment of temperature is $200\,K$ . Its cooling rate is $H$ . If its temperature reduced to $400\,K$ then cooling rate in same environment will become

  • A

    $(3/16)H$

  • B

    $(16/3)H$

  • C

    $(9/27)H$

  • D

    $(1/16)H$

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