The resistance of a wire of iron is 10 ohms and temp. coefficient of r – McqOptions

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1.	The resistance of a wire of iron is 10 ohms and temp. coefficient of resistivity is \[5\times {{10}^{-3}}/{}^\circ C\]. At \[20{}^\circ C\] it carries 30 milliamperes of current. Keeping constant potential difference between its ends, the temperature of the wire is raised to \[120{}^\circ C\]. The current in milliamperes that flows in the wire is [MP PMT 1994]
A.	20
B.	15
C.	10
D.	40
Answer» B. 15

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