A magnet is moved quickly into a coil of wire, inducing an EMF. According to Lenz's Law, the direction of the induced current will:
Correct answer: B. Oppose the change in magnetic flux
- A. Aid the change in magnetic flux
- B. Oppose the change in magnetic flux
- C. Be parallel to the magnetic field
- D. Be independent of the magnet's motion
Explanation
Lenz's Law states that the induced current will flow in a direction that opposes the change in magnetic flux that caused it (energy conservation principle).
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About Electromagnetism
Magnetic flux density and magnetic flux describe the strength of a magnetic field and the field passing through a surface. A charged particle moving through a magnetic field experiences a force perpendicular to its velocity and may follow circular or helical motion, depending on the angle between velocity and field.
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