Lenz's Law Physics Example 2
Follow the full solution, then compare it with the other examples linked below.
Example 2
mediumA circular loop is in a magnetic field pointing into the page. The field strength decreases. According to Lenz's law, in which direction does the induced current flow?
Solution
- 1 The flux into the page is decreasing.
- 2 Lenz's law: the induced current must oppose the decrease, so it must try to maintain the flux into the page.
- 3 By the right-hand rule, a current flowing clockwise (when viewed from the front) creates a magnetic field into the page, opposing the decrease.
Answer
When the magnetic flux through a loop decreases, the induced current flows in a direction that creates a magnetic field to replace the lost flux. The induced current always opposes the change, not the flux itself.
About Lenz's Law
The direction of an induced current is always such that it opposes the change in magnetic flux that produced it.
Learn more about Lenz's Law âMore Lenz's Law Examples
Example 1 easy
A north pole of a magnet is pushed toward a coil. According to Lenz's law, what pole does the coil's
Example 3 mediumA conducting ring is dropped through a region of magnetic field. As it enters the field, the induced
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