{"id":1383,"date":"2024-02-17T19:44:55","date_gmt":"2024-02-17T14:14:55","guid":{"rendered":"https:\/\/lotusarise.com\/qna\/?p=1383"},"modified":"2024-04-03T07:13:08","modified_gmt":"2024-04-03T01:43:08","slug":"q-consider-the-following-statements-49","status":"publish","type":"post","link":"https:\/\/lotusarise.com\/qna\/upsc\/q-consider-the-following-statements-49","title":{"rendered":"Q.\u00a0Consider the following statements:"},"content":{"rendered":"\n
    \n
  1. The Earth\u2019s magnetic field has reversed every few hundred thousand years.<\/li>\n\n\n\n
  2. When the Earth was created more than 4000 million years<\/strong> ago, there was 54% oxygen and no carbon dioxide.<\/strong><\/li>\n\n\n\n
  3. When living organisms originated, they modified<\/strong> the early atmosphere of the Earth.<\/li>\n<\/ol>\n\n\n\n

    Which of the statements given above is\/are correct?<\/p>\n\n\n\n

      \n
    • 1 only<\/li>\n\n\n\n
    • 2 and 3 only<\/li>\n\n\n\n
    • 1 and 3 only<\/li>\n\n\n\n
    • 1, 2 and 3<\/li>\n<\/ul>\n\n\n\n
      \n

      Answer: (c) 1 and 3 only<\/strong><\/p>\n<\/blockquote>\n\n\n\n

      Notes<\/h5>\n\n\n\n
        \n
      • Earth\u2019s magnetic field<\/strong>\n
          \n
        • On the scale of a million years, the earth\u2019s magnetic fields has been found to reverse its direction.<\/li>\n\n\n\n
        • Scientists estimate reversals have happened at least hundreds of times over the past three billion years.<\/li>\n\n\n\n
        • Over the last 20 million years, magnetic north and south have flipped roughly every 200,000 to 300,000 years. The last of these major reversals occurred about 780,000 years ago.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
        • Early atmosphere<\/strong>\n
            \n
          • Earth\u2019s original atmosphere was rich in methane, ammonia, water vapour, and the noble gas neon, but it lacked free oxygen<\/strong>. It is likely that hundreds of millions of years separated the first biological production of oxygen by unicellular organisms and its eventual accumulation in the atmosphere.<\/li>\n\n\n\n
          • Between 4.5 and 2.5 billion years (the Archaean and Proterozoic time), the earliest secondary atmosphere contained carbon dioxide (CO2), methane (CH4), water vapor (H2O), carbon monoxide (CO), a little nitrogen (N), and hydrogen (H)<\/strong>. So Carbon dioxide is present.<\/li>\n\n\n\n
          • When living organisms originated, they did not affect the early atmosphere. However, according to the official answer key, the answer is 1 and 3 only.<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n
            \n
            \"Earth's<\/figure>\n<\/div>","protected":false},"excerpt":{"rendered":"

            Which of the statements given above is\/are correct? Answer: (c) 1 and 3 only Notes<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_kad_blocks_custom_css":"","_kad_blocks_head_custom_js":"","_kad_blocks_body_custom_js":"","_kad_blocks_footer_custom_js":"","_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":"","footnotes":""},"categories":[1,3],"tags":[44],"years":[55],"class_list":["post-1383","post","type-post","status-publish","format-standard","hentry","category-upsc","category-prelims","tag-science-and-tech","years-55"],"acf":[],"taxonomy_info":{"category":[{"value":1,"label":"UPSC"},{"value":3,"label":"Prelims"}],"post_tag":[{"value":44,"label":"Science and Tech"}],"years":[{"value":55,"label":"2018"}]},"featured_image_src_large":false,"author_info":{"display_name":"LotusArise","author_link":"https:\/\/lotusarise.com\/qna\/author\/team-lotusarise"},"comment_info":0,"category_info":[{"term_id":1,"name":"UPSC","slug":"upsc","term_group":0,"term_taxonomy_id":1,"taxonomy":"category","description":"","parent":0,"count":1269,"filter":"raw","cat_ID":1,"category_count":1269,"category_description":"","cat_name":"UPSC","category_nicename":"upsc","category_parent":0},{"term_id":3,"name":"Prelims","slug":"prelims","term_group":0,"term_taxonomy_id":3,"taxonomy":"category","description":"","parent":1,"count":1251,"filter":"raw","cat_ID":3,"category_count":1251,"category_description":"","cat_name":"Prelims","category_nicename":"prelims","category_parent":1}],"tag_info":[{"term_id":44,"name":"Science and Tech","slug":"science-and-tech","term_group":0,"term_taxonomy_id":44,"taxonomy":"post_tag","description":"","parent":0,"count":167,"filter":"raw"}],"_links":{"self":[{"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/posts\/1383","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/comments?post=1383"}],"version-history":[{"count":0,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/posts\/1383\/revisions"}],"wp:attachment":[{"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/media?parent=1383"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/categories?post=1383"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/tags?post=1383"},{"taxonomy":"years","embeddable":true,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/years?post=1383"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}