Concept explainers
Consider the magnetic field due to the current in the wire shown in Figure 29.2. Rank the points A, B, and C in terms of magnitude of the magnetic field that is due to the current in just the length element
Figure 29.2 (Quick Quiz 29.1) Where is the magnetic field due to the current element the greatest?
Answer to Problem 30.1QQ
Explanation of Solution
Formula to calculate the magnetic field due to the current flow through a small length element is,
Here,
From the equation (1), it is clear that the magnetic field due to the current flow is inversely proportional to the square of the distance between the point to the small length element and directly proportional to the cross product of the vectors
The point A lies in the direction of the small length element of the wire. So, the angle between the vectors
The distance between the point
Thus, from the greatest to least order the magnetic field is maximum at point
Conclusion:
Therefore, the rank of the points
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Chapter 30 Solutions
Physics For Scientists And Engineers, Technology Update, Loose-leaf Version
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