Have you ever used a cloth potholder to grab the handle of a hot iron frying pan? Or wondered why copper electric wires all have plastic coatings? It turns out that the materials these items are made of---cloth, iron, copper and plastic--were chosen for the ways that they interact with heat and electricity.
Watch this video to learn how some materials transfer energy quickly, while others slow it down. Then, answer the question under Take Notes, below.
You may read the transcript to the video, and watch it as many times as you like.
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When it comes to thermal energy, it’s all about the heat. What brings it, what shades it, and how fast it transfers.
That’s where materials come in. Some materials, like iron and other metals, transfer heat quickly. They’re called conductors, and they get really hot, really fast.
Wood and other insulators, like glass, slow down the transfer of heat, and stay cooler longer, which is the reason you’re better off grabbing a wooden handle on a hot stove, and keeping hands off the metal.
Speaking metal conductors and not touching them, one really great idea is to stay away from these. (live electric wires sparking)
Electricity is another type of energy, and live bare wires are awesome at transferring it--- which is why they’re usually covered with rubber or plastic insulators.
There’s more to life than conductors and insulators, but when it comes to materials and energy transfer, understanding them comes in handy, so you know where not to be when lightning strikes.
In this lesson you will learn some basic information about how materials respond to heat and electric energy differently. After viewing the video on this page, you'll watch 1) an animation that describes in more detail the differences between conductors and insulators and 2) an animation that explains how materials expand and contract depending on the amount of thermal energy (heat) that is present. After taking notes and online quizzes, you’ll have a chance to review and organize what you’ve learned. Then you will produce your own project in which you’ll describe how the properties of materials make them more or less suitable for different jobs.
Answer the following questions in the box below. (Click SAVE when you have finished. To see your saved or submitted work again, click MY WORK at the top of the page.)
1) Name two types of energy.
2) List two types of materials that respond differently to energy.