A long straight wire carries 5.0 A. Compute the magnetic field 0.10 m away, in units of 10⁻⁶ T, using μ0 = 4π × 10⁻⁷ T m/A. Give the answer to one decimal place.

Practice question · Numerical answer

A long straight wire carries 5.0 A. Compute the magnetic field 0.10 m away, in units of $10^{-6}$ T, using $\mu_0 = 4\pi \times 10^{-7}$ T m/A. Give the answer to one decimal place.

Hints

Use the long-straight-wire result from Ampere’s law.
Compute (4pi x 1e-7 x 5.0) / (2pi x 0.10).

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10 (answers within ±0.3 count)

Why

$B = \mu_0 I/2\pi r = (4\pi \times 10^{-7} \times 5.0)/(2\pi \times 0.10) = 1.0 \times 10^{-5}$ T $= 10.0 \times 10^{-6}$ T, about a fifth of the Earth’s field.

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A long straight wire carries 5.0 A. Compute the magnetic field 0.10 m away, in units of 10−610^{-6}10−6 T, using μ0=4π×10−7\mu_0 = 4\pi \times 10^{-7}μ0​=4π×10−7 T m/A. Give the answer to one decimal place.

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More questions on Magnetostatics in Vacuum

A long straight wire carries 5.0 A. Compute the magnetic field 0.10 m away, in units of $10^{-6}$ T, using $\mu_0 = 4\pi \times 10^{-7}$ T m/A. Give the answer to one decimal place.