{"id":719,"date":"2023-09-27T06:41:05","date_gmt":"2023-09-27T06:41:05","guid":{"rendered":"http:\/\/localhost\/ecole9ja\/?p=719"},"modified":"2023-09-27T06:57:13","modified_gmt":"2023-09-27T06:57:13","slug":"week-3-jss-2-first-term-basic-technology-lesson-notes","status":"publish","type":"post","link":"https:\/\/ecolebooks.com\/nigeria\/posts\/week-3-jss-2-first-term-basic-technology-lesson-notes\/","title":{"rendered":"Week 3 – Jss 2 First Term Basic Technology Lesson Notes"},"content":{"rendered":"

week 3; materials and uses
\nwood; For small forests, see\u00a0Woodland. For wood as a commodity, see\u00a0timber. For other uses, see\u00a0Wood (disambiguation).
\n<\/em>“Wooden” and “Heartwood” redirect here. For other uses, see\u00a0Wooden (disambiguation)\u00a0and\u00a0Heartwood (disambiguation).
\n<\/em><\/p>\n

\n\n\n\n
\"\"
\n\t\t\t\t\t\t\tPine
\nSpruce
\nLarch
\nJuniper
\nAspen
\nHornbeam
\nBirch
\nAlder
\nBeech
\nOak
\nElm
\nCherry
\nPear
\nMaple
\nLinden
\nAsh<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

Wood<\/strong>\u00a0is a porous and fibrous structural tissue found in the\u00a0stems\u00a0and roots of\u00a0trees\u00a0and other\u00a0woody plants. It is an\u00a0organic material, a natural\u00a0composite\u00a0of\u00a0cellulose\u00a0fibers that are strong in tension and embedded in a\u00a0matrix\u00a0of\u00a0lignin\u00a0that resists compression. Wood is sometimes defined as only the secondary\u00a0xylem\u00a0in the stems of trees,[1]<\/sup>\u00a0or it is defined more broadly to include the same type of tissue elsewhere such as in the roots of trees or shrubs.[citation needed<\/em>]<\/sup>\u00a0In a living tree it performs a support function, enabling woody plants to grow large or to stand up by themselves. It also conveys water and\u00a0nutrients\u00a0between the\u00a0leaves, other growing tissues, and the roots. Wood may also refer to other plant materials with comparable properties, and to material engineered from wood, or wood chips or fiber.
\nWood has been used for thousands of years for\u00a0fuel, as a\u00a0construction material, for making\u00a0tools\u00a0and\u00a0weapons,\u00a0furniture\u00a0and\u00a0paper, and as a feedstock for the production of purified cellulose and its derivatives, such as\u00a0cellophane\u00a0and\u00a0cellulose acetate.
\nIn 2005, the growing stock of\u00a0forests\u00a0worldwide was about 434 billion cubic meters, 47% of which was commercial.[2]<\/sup>\u00a0As an abundant,\u00a0carbon-neutral\u00a0renewable resource, woody materials have been of intense interest as a source of renewable energy. In 1991 approximately 3.5 billion cubic meters of wood were harvested. Dominant uses were for furniture and building construction.[3]<\/sup>
\n\t\t\tContents
\n<\/strong>\u00a0\u00a0[hide]\u00a0<\/p>\n

    \n
  • \n
    1History\n<\/div>\n<\/li>\n
  • \n
    2Physical properties\n<\/div>\n
      \n
    • \n
      2.1Growth rings\n<\/div>\n<\/li>\n
    • \n
      2.2Knots\n<\/div>\n<\/li>\n
    • \n
      2.3Heartwood and sapwood\n<\/div>\n<\/li>\n
    • \n
      2.4Color\n<\/div>\n<\/li>\n
    • \n
      2.5Water content\n<\/div>\n<\/li>\n
    • \n
      2.6Structure\n<\/div>\n<\/li>\n
    • \n
      2.7Earlywood and latewood\n<\/div>\n
        \n
      • \n
        2.7.1In softwood\n<\/div>\n<\/li>\n
      • \n
        2.7.2In ring-porous woods\n<\/div>\n<\/li>\n
      • \n
        2.7.3In diffuse-porous woods\n<\/div>\n<\/li>\n<\/ul>\n<\/li>\n
      • \n
        2.8Monocot wood\n<\/div>\n<\/li>\n
      • \n
        2.9Specific gravity\n<\/div>\n<\/li>\n
      • \n
        2.10Wood density\n<\/div>\n<\/li>\n<\/ul>\n<\/li>\n
      • \n
        3Hard and soft woods\n<\/div>\n<\/li>\n
      • \n
        4Chemistry of wood\n<\/div>\n
          \n
        • \n
          4.1Extractives\n<\/div>\n<\/li>\n<\/ul>\n<\/li>\n
        • \n
          5Uses\n<\/div>\n
            \n
          • \n
            5.1Fuel\n<\/div>\n<\/li>\n
          • \n
            5.2Construction\n<\/div>\n
              \n
            • \n
              5.2.1Wood flooring\n<\/div>\n<\/li>\n
            • \n
              5.2.2Engineered wood\n<\/div>\n<\/li>\n<\/ul>\n<\/li>\n
            • \n
              5.3Furniture and utensils\n<\/div>\n<\/li>\n
            • \n
              5.4Next generation wood products\n<\/div>\n<\/li>\n
            • \n
              5.5In the arts\n<\/div>\n<\/li>\n
            • \n
              5.6Sports and recreational equipment\n<\/div>\n<\/li>\n<\/ul>\n

              uses of metals
              \nUses of metals
              \n<\/strong>We use different metals for different jobs as they have different properties: it’s important to choose the right metal for the job.
              \nChoosing the right metal for the job
              \n<\/strong><\/p>\n

              \n\n\n\n\n\n\n\n
              Metal<\/strong><\/td>\nProperties<\/strong><\/td>\nUses<\/strong><\/td>\n<\/tr>\n
              aluminium<\/strong>
              \n\t\t\t\t\t\t\t\t\t\"\"\/<\/td>\n              		low density, does not corrode<\/td>\nsuitable for the bodies of planes<\/td>\n<\/tr>\n
              copper<\/strong>
              \n\t\t\t\t\t\t\t\t\t\"\"\/<\/td>\n              		good conductor of electricity, does not react with water<\/td>\nelectrical wires as it is a good conductor
              \nwater pipes due to its low reactivity<\/td>\n<\/tr>\n
              gold<\/strong>
              \n\t\t\t\t\t\t\t\t\t\"\"\/<\/td>\n              		very good conductor of electricity, unreactive<\/td>\nelectrical connections on circuit boards – due to its conductivity
              \njewellery – due to its lack of reactivity<\/td>\n<\/tr>\n
              steel<\/strong>
              \n\t\t\t\t\t\t\t\t\t\"\"\/<\/td>\n              		cheap and strong<\/td>\nsuitable for building material<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

              When you answer questions on properties of metals it’s important to make sure that the property you give is relevant to the use you’ve been asked about: eg, copper is unreactive with water but that is not relevant if the question asks you about its use in electrical wires.
              \nquestion<\/p>\n

                \n
              • list 5 uses of wood\n<\/li>\n
              • list 5 uses of metals\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"

                week 3; materials and uses wood; For small forests, see\u00a0Woodland. For wood as a commodity,…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1,86],"tags":[],"class_list":["post-719","post","type-post","status-publish","format-standard","hentry","category-posts","category-first-term-jss-2-basic-technology"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts\/719","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/comments?post=719"}],"version-history":[{"count":1,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts\/719\/revisions"}],"predecessor-version":[{"id":720,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts\/719\/revisions\/720"}],"wp:attachment":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/media?parent=719"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/categories?post=719"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/tags?post=719"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}