Physics · Magnetism and Electromagnetic Induction
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When the area vector A is parallel to the magnetic field B, what is the value of magnetic flux (θ/B)?
- A
0
- B
BA cos 0
- C
BA cos 90
- D
B/A
The magnetic flux (Φ) through a surface is given by the formula Φ = B * A * cos(θ), where B is the magnetic field strength, A is the area through which the field lines pass, and θ is the angle between the area vector and the magnetic field vector. When the area vector A is parallel to the magnetic field B, the angle θ is 0 degrees. Thus, cos(0) = 1, and the magnetic flux simplifies to Φ = BA.
Option A (0) is incorrect as it implies no magnetic flux, which only occurs when θ is 90 degrees. Option C (BA cos 90) is also incorrect since it leads to zero flux for a perpendicular orientation. Option D (B/A) does not accurately reflect the relationship between the variables involved in calculating magnetic flux.
This option suggests that the magnetic flux is zero, which is incorrect. Magnetic flux is only zero when the area vector is perpendicular to the magnetic field (90 degrees).
This is the correct answer. When the area vector A is parallel to the magnetic field B, the angle θ is 0 degrees. Thus, cos(0) = 1, making the magnetic flux equal to BA.
This option is incorrect because cos(90) = 0. This implies no magnetic flux when the area vector is perpendicular to the magnetic field.
This option does not represent magnetic flux correctly. It misrepresents the relationship between magnetic field, area, and flux.
Tagged under Physics · Magnetism and Electromagnetic Induction · 2025