A constant potential difference is applied to the ends of a graphite rod, whose resistance decreases with a rise of temperature. The rod can be $(1)$ covered with asbestos or $(2)$ left open to atmosphere. Answer for steady state.

  • A

    in both cases power lost is same but temperature of rod is more in case- $1$

  • B

    in case- $1$ power lost as well as temperature of rod is more

  • C

    in case- $2$ power lost as well as temperature of rod is more

  • D

    in case- $1$ power lost is more but temperature of rod is less

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