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# Unit 2: How a microwave oven works?

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## Introduction

How do microwave ovens work? To explore this, we need to put together a few pieces, what electric dipoles are, how they behave in the presence of electric fields. But, let's get our basics right. In this lesson, we discuss the flow of the unit!

## Electric charges- what are they? And how do they behave?

Where does everything electric start? Electric charge! Let's see what they are, and what rules they obey!

## Why do balloons rubbed with hair stick to walls?

A balloon rubbed with hair, sticks to walls. Why? Learning about charge transfer through friction and induction can help us answer this question!

## Coulomb's law and why it's easy to beat gravity

Although a ball is pulled down by the mighty force of the entire Earth, I can easily counter it with my fingers. Why? How? Mindblown? Let's learn how to calculate electric force & compare it with gravity!

### Practice

#### Quiz 1

Level up on the above skills and collect up to 400 Mastery points

## Electric fields - How does one charge know of the presence of other charges?

Let's dig a little deeper now, how do charges attract each other from a distance. How do they know what's going on?

## What are electric dipoles and how do they behave in electric fields?

In this final lesson, we see how the electric fields in the microwave oven heat up food! It turns out we need to understand the concept of electric dipoles to fully grasp the picture, so we start with dipoles!

### Practice

#### Quiz 2

Level up on the above skills and collect up to 320 Mastery points
Up next for you:

#### Unit test

Level up on all the skills in this unit and collect up to 900 Mastery points!