Two rods (one semi-circular and other straight) of same material and of same cross-sectional area are joined as shown in the figure. The points $A$ and $B$ are maintained at different temperature. The ratio of the heat transferred through a cross-section of a semi-circular rod to the heat transferred through a cross section of the straight rod in a given time is

86-1

  • A

    $2 : \pi$

  • B

    $1:2$

  • C

    $\pi : 2$

  • D

    $3:2$

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  • [JEE MAIN 2021]