Conductors and Insulators: Materials That Transfer or Block Heat

Conductors and Insulators are important concepts that help us understand how heat flows through different materials. Some materials allow heat to pass easily, while others resist the flow of heat.

This concept is useful in everyday life, from cooking to designing clothes and buildings. In this article, we will understand what conductors and insulators are and their applications.

Table of Contents

• Understanding Conductors and Insulators
• Applications of Good Conductors of Heat
• Applications of Bad Conductors of Heat

Understanding Conductors and Insulators

Conduction is the most important mode of heat transfer in solids compared to liquids and gases. But it is not necessary that all solids will conduct heat because there are many solids that are poor conductors of heat. Materials that allow heat to pass through them easily are known as good conductors of heat. For instance, all metals like aluminium, iron and copper are conductors.

Whereas those materials which do not allow heat to pass through them easily are known as poor conductors (insulators) of heat. For instance, plastic, wood, and air are insulators.

Applications of Good Conductors of Heat

Now that we know which materials are good conductors, let’s see how they are used in daily life.

1. Cooking utensils are made of metals that are good conductors of heat, so that heat can be transferred to the food easily.
2. The base of an electric iron is made of metal as it is a good conductor of heat.
3. Water is used as a coolant in vehicles.
4. Mercury is used in thermometers as a thermometric liquid.
5. The head of the soldering machine is made of copper to heat quickly. 

Applications of Bad Conductors of Heat

Next, let’s look at how insulators help us stay safe and comfortable by resisting heat.

1. Handles of electric irons are made of plastic or wood because they are bad conductors of heat. They do not get hot and allow easy handling of hot utensils.
2. Beverages are stored in a vacuum flask, as the gap between the containers acts as an insulator
3. Bricks are used for building houses as they do not allow the exchange of heat. Thus, it reduces the heat that enters our houses in summer, and traps heat inside our houses in winter.
4. In colder countries, people stay in igloos as ice contains a large amount of trapped air, which acts as an insulator. Thus, it does not allow heat to escape and keeps the igloos warm.
5. Woollen clothes are used to keep us warm in winter because wool is an insulator.

Observe the animals and birds from cold countries. What do you observe? How are they different in appearance compared to normal animals? Why are they different?

Animals and birds from cold countries usually have thick fur or feathers and a layer of fat (blubber) under their skin. They often appear larger, fluffier, and more rounded compared to animals in warmer regions. Many also have shorter ears and tails, which reduces heat loss.

They are different because these features, such as the conductor and insulator, such as air (which acts as an insulator), and the fat layer, prevent heat from escaping, helping them survive in cold climates.

Till now, we have learned that conductors and insulators are materials that behave differently when it comes to heat. Conductors allow heat to pass through them easily, like metals such as copper, iron, and aluminium. Insulators, on the other hand, resist the flow of heat, such as wood, plastic, air, and wool.