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Which rule gives the direction of the magnetic field around a straight wire carrying a current?
AThe Left Hand Rule
BThe Inverse Square Rule
CThe Parallel Axis Rule
DThe Right Hand Rule
Answer & Solution
Correct answer: D. The Right Hand Rule
1. Grip the wire with the thumb pointing along the direction of conventional current.
2. The curled fingers of the right hand then point the way the field lines run.
3. This method is called the Right Hand Rule.
4. Using the left hand always gives the wrong answer, because the two hands cannot be rotated onto each other.
_Source: Siyavula Physical Sciences Grade 11 (Everything Science, CC BY 4.0), Chapter 10: Electromagnetism_
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