Page 72 - ScienceStd4

(a) Combustion produces energy for cooking, heating, and
running various machines. For example, gas combustion
in stoves provides energy for cooking food, as shown in
Figure 2;
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Figure 2: Cooking

(b) Combustion is used in industries for various activities. It

includes smelting iron and producing items such as steel
bars and plastics. Fire is also used in smelting gold;

(c) The heat generated from the process combustion helps
dry and preserve foods and crops; and

(d) The heat generated from combustion helps us during cold
weather. For example, we can warm our bodies with heat
from fire during cold weather as shown in Figure 3.

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