Concept explainers
(a)
The magnitude of the electric field in the wire.
(a)
Answer to Problem 49P
The magnitude of the electric field in the wire is
Explanation of Solution
Write the expression for resistance of a wire.
Here,
Write the expression for the area of the wire.
Here,
Write the expression for potential difference.
Here,
Write the expression for electric field along the wire.
Here,
Conclusion:
Substitute
Substitute
Substitute
Substitute
Therefore, the magnitude of the electric field in the wire is
(b)
The power delivered to the wire.
(b)
Answer to Problem 49P
The power delivered to the wire is
Explanation of Solution
Write the expression for the power delivered to the wire.
Here,
Conclusion:
Substitute
Therefore, the power delivered is
(c)
The power delivered to the wire if the temperature is increased to
(c)
Answer to Problem 49P
The power delivered to the wire after temperature change is
Explanation of Solution
Write the expression for the resistance of the wire after change in temperature.
Here,
Write the expression for power delivered to the wire after temperature change.
Here,
Conclusion:
Substitute
Substitute
Therefore, the power delivered to the wire after temperature change is
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Chapter 27 Solutions
Physics: for Science.. With Modern. -Update (Looseleaf)
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