# Lesson Plan: Electromagnetic Interactions between Straight Conductors Physics

This lesson plan includes the objectives, prerequisites, and exclusions of the lesson teaching students how to determine the magnetic forces between parallel lines of current and analyze the net magnetic fields of the currents.

#### Objectives

Students will be able to

• use diagrams of the magnetic fields around conducting wires to qualitatively determine the net magnetic field of two parallel conducting wires carrying currents in the same and in opposite directions,
• use the formula to relate the force per unit length between two parallel conducting wires to their perpendicular separation and the currents that they carry,
• for two parallel conducting wires carrying currents in the same and in opposite directions, use the direction of the net magnetic field at a point midway between the wires to determine whether the net force between the wires is attractive or repulsive,
• qualitatively determine the net magnetic field due to arrays of parallel conducting wires.

#### Prerequisites

Students should already be familiar with

• the magnetic field produced by a single conducting wire,
• the formula for the force on a straight wire in a uniform magnetic field, .

#### Exclusions

Students will not cover

• curved wires.