Page 2 - Lesson Notes
P. 2

  Plastic is strong, light and durable:
                            Plastics being less dense are lighter than metals.
                            Therefore, they are used in cars, aircrafts and spacecraft.
                            Plastics  is  of  lower  price,  lightweight  and  also  have  good  strength  and  are
                              long-lasting.
                            This makes it suitable for storing of food, water, milk, jams, pickles, squashes
                              and soft drinks, etc.



        BIODEGRADABLE AND NON-BIODEGRADABLE MATERIALS:


            1.  Biodegradable:
               A  substance  which  gets  decomposed  through  natural  processes,  such  as  action  by

               bacteria, is called biodegradable. Examples: peels of vegetables, food stuffs, fruit, paper,

               cotton cloths, wood, etc. These materials are environmental friendly, as they rot away with
               time and do not cause pollution.
























            2.  Non-biodegradable:
               A substance which is not easily decomposed or takes many years to get decomposed by

               natural processes is termed as non-biodegradable. Examples: tin, aluminium, plastics, etc.

               These are not environmental friendly, as they do not rot and cause pollution.
























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