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# Unit 4: Work & Energy

In this chapter, we will define the terms 'work' and 'energy'. We will learn how to calculate them, and use them to look at our world in a very different way.

## Work

Work is a very common term in our daily language. But in physics work has a specific meaning. Let's explore what that is.

## Energy

Let's explore what energy and it's different forms are.

## Work energy theorem

In this lesson, we will see the connection between work and kinetic energy.

## Law of conservation of energy

Let us explore the law of conservation of energy and see how to use it in problem-solving.

## Power

Sometimes we not only care about how much work is done but also how fast that work is done. This concept is called power. Let's explore power in this lesson

## Commercial unit of energy

If you take a look at the electricity bill, you don't see joules or energy. You only see 'units'. What are these units? Why do electric companies measure electricity in terms of these 'units'? In this lesson, we will explore this question.