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Unit 4: Work & Energy

About this unit

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 is a very common term in our daily language. But in physics work has a specific meaning. Let's explore what that is.
Let us explore the law of conservation of energy and see how to use it in problem-solving.
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
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.