Concept explainers
A circular loop of wire is held in a uniform magnetic field, with the plane of the loop perpendicular to the field lines. Which of the following will not cause a current to be induced in the loop? (a) crushing the loop (b) rotating the loop about an axis perpendicular to the field lines (c) keeping the orientation of the loop fixed and moving it along the field lines (d) pulling the loop out of the field
Answer to Problem 31.1QQ
Explanation of Solution
According to Lenz’s law, anything that causes the change in magnetic field induces current. Since the loop of wire is held in a uniform magnetic field, by keeping the orientation fixed no current will induced in the given loop.
Conclusion:
Since, the orientation of the loop is fixed there will not be any current induced in the loop. Thus, option (c) is correct.
By crushing the loop, the magnetic field will get disturbed and therefore the current will be induced. Thus, option (a) is incorrect.
By rotating the loop about an axis, the magnetic field will change and therefore the current will be induced. Thus, option (b) is incorrect.
By pulling the loop out of field, the path of magnetic field will change and causes current to be induced. Thus, option (d) is incorrect.
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Chapter 31 Solutions
Physics for Scientists and Engineers, Technology Update (No access codes included)
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