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 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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- [AIPMT 2005]
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- [IIT 1988]