A metal rod $\mathrm{AB}$ of length $10 x$ has its one end $\mathrm{A}$ in ice at $0^{\circ} \mathrm{C}$ and the other end $\mathrm{B}$ in water at $100^{\circ} \mathrm{C}$. If a point $\mathrm{P}$ on the rod is maintained at $400^{\circ} \mathrm{C}$, then it is found that equal amounts of water and ice evaporate and melt per unit time. The latent heat of evaporation of water is $540 \ \mathrm{cal} / \mathrm{g}$ and latent heat of melting of ice is $80 \ \mathrm{cal} / \mathrm{g}$. If the point $\mathrm{P}$ is at a distance of $\lambda x$ from the ice end $\mathrm{A}$, find the value of $\lambda$.

[Neglect any heat loss to the surrounding.|

  • [IIT 2009]
  • A

    $4$

  • B

    $5$

  • C

    $9$

  • D

    $2$

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  • [AIIMS 1998]