Practice question · Select all that apply
Which results follow from Ampère’s law applied to symmetric geometries?
Hints
- Three are magnetostatic results; one belongs to electrostatics.
- Ampere’s law says nothing about static charges.
Show the answer
- A. The field inside a long solenoid is uniform
- B. The field of a long straight wire falls as one over the distance
- C. The field inside a toroid falls as one over the radius
Why
The wire, solenoid and toroid all follow from Ampère’s law with the right loop. The inverse-square law for a point charge comes from Gauss’s law and has nothing to do with currents.
Practise Magnetostatics in Vacuum
The app has 4 more questions on this lesson, and keeps your place in the course. Physics II is free to start.
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 μ0 = 4π…
- Sort each consequence by why it holds: because the magnetic field has zero divergence, or because it is the…
- An Amperian loop drawn entirely outside a long solenoid encloses zero net current, so the field just inside…
- Complete the comparison between the three symmetric magnetostatic geometries.
- A current loop of magnetic moment 0.5 A m² sits in a 0.4 T field with its moment perpendicular to the field.…
- Match each magnetostatic tool to what it is best used for.
- The magnetic field has zero divergence, whereas the static electric field has zero curl. What fundamental…