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A long length of copper wire is initially at room temperature (23∘C) when it is connected across the terminals of an ideal potential source of V0=10V. The power dissipated by the wire as heat is initially measured to be Pinitial = 50W. The wire begins to heat up, but eventually reaches a "steady state" temperature (i.e., the wire is now warmer than the original room temperature, but it is no longer getting any hotter.) At this point, the power dissipated by the same circuit is Pfinal = 44.3 W. Calculate the final temperature of the copper wire. (You can find the temperature coefficient of resistivity for copper from the table in the text above.)
Given:
- The initial temperature of copper wire is .
- The voltage of potential source is .
- The initial power dissipated by wire is .
- The final power dissipated by wire is .
The formula to calculate the initial resistance of the wire is,
Here, R0 is the initial resistance, V0 is the voltage of source and Pinitial is the initial power dissipated by wire.
Substitute the known values in the formula to calculate the initial resistance of the wire.
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