#Magnetism and Current-Carrying Wires

Hey there, future AP Physics 2 master! Let's dive into the fascinating world of magnetism and current-carrying wires. Remember, it's all about the interplay between electricity and magnetism, and how they create forces and fields. Let's get started!

#Magnetic Field Produced by a Current-Carrying Wire

This is a core concept, and you'll see it pop up in multiple contexts. Make sure you understand both the field's direction and strength.

#Basics

• Current-carrying wires are like tiny magnets 🧲. They create magnetic fields around them.
• The magnetic field lines form concentric circles around the wire, perpendicular to it.
• The magnetic field vector is always tangent to these circles.
• There's no magnetic field component pointing towards, away from, or parallel to the wire itself.

#Field Strength

• The strength of the magnetic field depends on two main things:
  • Current (I): More current = stronger field (directly proportional).
  • Distance (r): Closer to the wire = stronger field (inversely proportional).

• Use this formula to calculate the magnetic field strength (B) near a long, straight wire:

  $$B=\frac{\mu_{0}}{2 \pi} \frac{I}{r}$$

  • $B$ = magnetic field strength (in Teslas, T)
  • $\mu_0$ = permeability of free space constant (a given constant, don't memorize it!)
  • $I$ = current in the wire (in Amperes, A)
  • $r$ = perpendicular distance from the wire (in meters, m)

#Direction of the Magnetic Field

• For a current loop, the magnetic field at its center points along the loop's axis. Use RHR1 to find the specific direction.
• When you have ...