In this article, you will learn to describe the effects of heat on objects.
Heat transfer from hot object to a cold object. What do you think will happen to objects when heat flows to them? In this article, you will learn three different ways on the effect of heat on objects: change in temperature, and change in size and change in state.
Change in temperature. When heat flows to a cold object, the cold object becomes hot. Hotness or coldness describes the temperature of an object. A thermometer is used to measure temperature in degrees Celsius (°C) or degree Fahrenheit (°F). A change in temperature can be illustrated while boiling water. As the flame of the alcohol lamp flowed through the water, its particles moved faster. The fast movement of particles made the water to rise its temperature.
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Change in size. Place a balloon and thermometer in a hot water. The balloon looked bigger when it is placed in hot water because, when the air inside it was heated, its tiny particles moved faster. This fast movement made the particles occupies more space, so the air expanded. To expand means to become bigger. The same thing happened to the liquid inside the thermometer, and so we can observe the liquid rose when the thermometer is heated. When you removed the balloon and the thermometer from the hot water, the air and the liquid contracted or become smaller. Liquids and gasses expand when they are heated and contact when they are cooled. Do you see the gaps in cemented roads? These are provisions for the expansion of the materials when the temperature rises.
Change in state. Matter may be solid, liquid or gas. Can the state of matter be changed by heat? Get three ice cubes, alcohol lamp, tripod and a pan. Place the ice cubes in the pan and place it over the alcohol lamp. Observe what happens to the ice cubes and continue heating the pan until the water disappears. In this simple experiment, we know that the ice cubes are solid. As it is heated, it changes into water which is liquid. Further heating shows that the water disappeared and has evaporated or changed into gas. All these happened due to heat.
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Furthermore, an additional example on how heat affects object can be seen on steel used in constructing buildings and bridges. The steel expands and contract due to temperature changes. Engineers build structures with expansion points to allow the materials to expand without causing any damage to these structures.