### At a Glance

• STEM
• Physics

#### Instructional Level

• College & CEGEP
• University

#### Course

• Electricity and Magnetism

#### Social Plane(s)

• Individual
• Group

• Collecting & seeking information
• Solving problems
• Analyzing

### Technical Details

• EdEX

#### Class size

• Large (100-250)

#### Time

• Brief segment of class period (< 20 mins)

#### Instructional Purpose

• Preparation & knowledge activation

## Overview

In this worksheet activity, students are introduced to the concept of flux, in particular electric flux. The aim of the activity is to prepare for future learning by having students recognize important features and having them pay attention to the relation between the field lines and the area. Students will observe 6 scenarios given of rain falling on a house (the angle/number of the windows varies as does the angle of the rain). Students will then be asked in-class to invent one equation using words that describes how much rain would end up in each house for all six cases. The instructor follows up with a discussion of the equation, which can be viewed as an example of flux. Then the concepts of area vector and electric flux are introduced drawing on analogies with the rainfall example. This activity benefits students as it gives them analogies to instinctually understand the more abstract Gauss’ law.

## Instructional Objectives

Students will be able to:

• Build a flux equation
• Make connections between a real-world scenario and the representation in an equation

## Contributor's Notes

### Georg Rieger

University of British Columbia

Benefits
Tips
Benefits
• Builds on everyday experiences to provide an intuitive understanding of flux
• Students learn to make a connection between concepts and mathematics
• Introduces the electric flux equation when students are prepared for it by building on the much more intuitive rain flux. It thus provides meaning to a fairly abstract concept.
Tips
• Give questions in class to check in with students and make sure that they understood the analogy. This can be in the form of the scaffolded worksheet or the clicker questions.