A solenoid of 500 turns, length 0.4 m, carries 5 A. The magnetic flux through a single turn at the center is (μ₀ = 4π × 10⁻⁷ T·m/A, A = 0.01 m²):
Correct answer: B. 1.57 × 10⁻⁴ Wb
- A. 7.85 × 10⁻⁵ Wb
- B. 1.57 × 10⁻⁴ Wb
- C. 3.14 × 10⁻⁴ Wb
- D. 6.28 × 10⁻⁴ Wb
Explanation
B = μ₀nI = (4π × 10⁻⁷)(500/0.4)(5) ≈ 7.85 × 10⁻³ T. Flux Φ = BA = 7.85 × 10⁻³ × 0.01 = 1.57 × 10⁻⁴ Wb.
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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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