Concept explainers
(a)
The estimation of the resistivity and
(a)
Answer to Problem 28PQ
The estimation of the resistivity and conductivity of a roll of the pure copper pennies are
Explanation of Solution
The estimated values of pure substances are given in Table 28.2.
For the pure copper, the resistivity
Conclusion:
Therefore, the estimation of the resistivity and conductivity of a roll of the pure copper pennies are
(b)
The estimation of the resistance of the roll of pure copper pennies.
(b)
Answer to Problem 28PQ
The estimation of the resistance of the roll of pure copper pennies is
Explanation of Solution
The radius and the length of a stack of 50 pennies are
Write the relation for the resistance of the role of pure copper pennies.
Here,
Write the relation for the cross-sectional area of the copper penny.
Here,
Use equation (II) in equation (I) to get
Conclusion:
Substitute
Therefore, the estimation of the resistance of the roll of pure copper pennies is
(b)
The estimation of the resistance of the roll of pure aluminum pennies.
(b)
Answer to Problem 28PQ
The estimation of the resistance of the roll of pure aluminum pennies is
Explanation of Solution
Rewrite the equation (III) for the resistance of the aluminum pennies
Conclusion:
Substitute
Therefore, the estimation of the resistance of the roll of pure aluminum pennies is
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Chapter 28 Solutions
Physics for Scientists and Engineers: Foundations and Connections
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