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Magnetic Field Equation:
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The magnetic field equation \( B = \frac{\mu_0 \cdot I}{2 \pi r} \) calculates the magnetic field strength around a straight current-carrying wire. This fundamental equation in electromagnetism describes how the magnetic field decreases with distance from the wire.
The calculator uses the magnetic field equation:
Where:
Explanation: The equation shows that magnetic field strength is directly proportional to the current and inversely proportional to the distance from the wire.
Details: Calculating magnetic field strength is essential for designing electrical systems, understanding electromagnetic phenomena, and ensuring safety in electrical installations where magnetic fields may affect equipment or human health.
Tips: Enter current in amperes and distance in meters. Both values must be positive numbers greater than zero for accurate calculation.
Q1: What is the permeability of free space (μ₀)?
A: μ₀ is a physical constant equal to 4π × 10⁻⁷ T·m/A, representing the measure of resistance encountered when forming a magnetic field in a vacuum.
Q2: Does this equation work for all wire configurations?
A: No, this specific equation applies only to straight, infinitely long wires. Different configurations (loops, solenoids) have different equations.
Q3: How does distance affect magnetic field strength?
A: Magnetic field strength decreases inversely with distance from the wire - doubling the distance halves the field strength.
Q4: What are typical magnetic field strengths?
A: Earth's magnetic field is about 25-65 μT. Household appliances may produce fields from 0.1 μT to several mT near the source.
Q5: Are there safety considerations for magnetic fields?
A: Yes, prolonged exposure to strong magnetic fields may have health implications. Various safety standards exist for maximum exposure limits.