Question

Linus builds an electrical circuit with a battery and with wires that carry the current. As the battery weakens, the current also weakens.

How does this affect the magnetic field around the wires?

1The field gets stronger.
2The field gets weaker.
3The field changes direction.
4The field disappears completely.

Answer 1

I think the correct answer from the choices listed above is option 2. As the battery weakens, the current also weakens. This affect the magnetic field around the wires in a way that the  field gets weaker. Hope this answers the question. Have a nice day.

Answer 2

Answer:

2 The field gets weaker.

Explanation:

The magnetic field produced by a current-carrying wire is given by:

$B=\frac{\mu_0 I}{2 \pi r}$

where

$\mu_0$ is the vacuum permeability

$I$ is the current in the wire

$r$ is the distance from the wire

In this problem, the battery weakens, so the current through the wire decreases. As $I$ (the current) is on the numerator in the formula, it means that the value of the fraction decreases, so the magnetic field gets weaker (in fact, the magnetic field is directly proportional to the current, so as the current decreases, the intensity of the field decreases as well).