{"id":1841,"date":"2013-10-08T04:50:58","date_gmt":"2013-10-08T04:50:58","guid":{"rendered":"http:\/\/www.worldofmastermind.com\/?p=1841"},"modified":"2017-10-30T00:35:22","modified_gmt":"2017-10-30T00:35:22","slug":"%e5%8f%a4%e5%9f%83%e5%8f%8a%e4%ba%ba%e5%a6%82%e4%bd%95%e6%96%bc%e4%b8%80%e5%b0%8f%e6%99%82%e5%85%a7%ef%bc%8c%e8%ad%89%e6%98%8e%e5%9c%b0%e7%90%83%e6%98%af%e5%9c%93%e5%bd%a2%e7%9a%84%ef%bc%8c%e5%8f%8a","status":"publish","type":"post","link":"https:\/\/www.worldofmastermind.com\/?p=1841","title":{"rendered":"\u53e4\u5e0c\u81d8\u4eba\u5982\u4f55\u65bc\u4e00\u5c0f\u6642\u5167\uff0c\u8b49\u660e\u4e86\u5730\u7403\u662f\u5713\u5f62\u7684\uff0c\u53ca\u4e08\u91cf\u4e86\u5730\u7403\u7684\u5713\u5468?"},"content":{"rendered":"

How Ancient Greek Showed that Earth is Round, And Measured Earth’s Circumference within one hour? <\/strong>\u00a0\u00a0 \u4fe1\u5805\u00a0 10\/7\/2013<\/strong>
\"Earth\"<\/a> \u00a0\u00a0 \"shadow\"<\/a>
\u524d\u8a00: \u4fe1\u5805\u5728\u6b64\u7e7c\u7e8c\u89e3\u8aaa “\u65e5\u4e2d\u7acb\u8289\u6e2c\u5f71”\u7684\u5999\u7528\u3002\u4e0a\u6587\u63d0\u53ca\u4e2d\u570b\u7684\u8001\u7956\u5b97\uff0c\u7528\u4e00\u6839\u516b\u5c3a\u9577\u7684\u5713\u68cd\uff0c\u6e2c\u77e5\u4e00\u5e74\u6709365.25\u5929\uff0c\u5283\u51fa\u4e86\u4e8c\u5341\u56db\u500b\u7bc0\u6c23\u5faa\u74b0\uff0c\u53ca\u756b\u51fa\u592a\u6975\u9670\u967d\u5716\u3002(\u8acb\u770b \u592a\u6975\u9670\u967d\u5716\u7684\u7531\u4f86<\/a>)<\/strong><\/p>\n

\u6b64\u6587\u89e3\u8aaa\u5e7e\u5343\u5e74\u524d\uff0c\u53e4\u5e0c\u81d8\u4eba\uff0c\u4e5f\u662f”\u65e5\u4e2d\u7acb\u8289\u6e2c\u5f71”\uff0c\u65bc\u4e00\u5c0f\u6642\u5167\uff0c\u8b49\u660e\u4e86\u5730\u7403\u662f\u5713\u5f62\u7684 (round)\uff0c\u4e26\u4e14\u4e08\u91cf\u4e86\u5730\u7403\u7684\u5713\u5468 (Earth circumference)\u3002<\/strong><\/p>\n

1972\u5e74\u4fe1\u5805\u525b\u51fa\u9053\uff0c\u5728UCLA (\u52a0\u5dde\u6d1b\u6749\u78ef\u5927\u5b78) \u6559\u57fa\u672c\u7269\u7406(Fundamental Physics)\u3002\u7576\u6642\u6211\u6700\u611b\u8b1b\u7684\u8ab2\u984c\u662f “\u53e4\u5e0c\u81d8\u4eba\u5982\u4f55\u65bc\u4e00\u5c0f\u6642\u5167\uff0c\u8b49\u660e\u5730\u7403\u662f\u5713\u5f62\u7684\uff0c\u4ee5\u53ca\u5982\u4f55\u4e08\u91cf\u5730\u7403\u7684\u5713\u5468? ”\u00a0 \u53e4\u5e0c\u81d8\u4eba\u8ddf\u6211\u5011\u8001\u7956\u5b97\u4e00\u6a23\uff0c<\/strong>\u65e5\u4e2d\u7acb\u8289\u6e2c\u5f71\u3002<\/strong>\u7528\u4e00\u6839\u5713\u67f1\uff0c\u7c21\u55ae\u7684\u5e7e\u4f55\uff0c\u53ca\u7c21\u55ae\u7684\u5929\u6587\u5e38\u8b58\uff0c\u5c31\u5f88\u5bb9\u6613\u7684\u89e3\u6c7a\u9019\u500b\u5927\u554f\u984c\u3002<\/strong><\/p>\n

\u9019\u8ab2\u984c\u7684\u555f\u793a\u662f\u5ff5\u7269\u7406\uff0c\u4e0d\u662f\u6b7b\u80cc\u5b9a\u5f8b\u8207\u7406\u89e3\u6df1\u5967\u7406\u8ad6\u3002\u4eba\u4eba\u90fd\u53ef\u6210\u70ba\u5049\u5927\u7684\u79d1\u5b78\u5bb6\uff0c\u5049\u5927\u7684\u767c\u73fe\uff0c\u90fd\u8d77\u6e90\u65bc\u4e00\u500b\u7c21\u55ae\u7684\u6982\u5ff5\u3002\u53ea\u8981\u554f\u5c0d\u4e86\u554f\u984c\uff0c\u5c31\u6709\u89e3\u7b54\u3002\u554f\u984c\u8ddf\u7b54\u6848\u662f\u4e00\u9ad4\u7684\u5169\u9762 (two sides of the same coin)\u3002\u627e\u4e0d\u5230\u7b54\u6848\u662f\u4f60\u4e0d\u5920\u8070\u660e\uff0c\u7f3a\u5c11\u667a\u6167\uff0c\u8981\u591a\u4fee\u5fc3\u990a\u6027\uff0c\u9748\u6027\u63d0\u6607\u4e86\uff0c\u667a\u6167\u81ea\u7136\u589e\u9577\u3002<\/strong><\/p>\n

2. \u6982\u5ff5\u53ca\u65b9\u6cd5<\/strong><\/span>
\u57c3\u62c9\u6258\u8272\u5c3c(Eratosthenes) \u662f\u53e4\u57c3\u53ca\u4e9e\u6b77\u5c71\u5927\u5716\u66f8\u9928\u7684\u7b2c\u4e09\u4efb\u9928\u9577\u3002\u4ed6\u6700\u6709\u540d\u7684\u8ca2\u737b\u4e4b\u4e00\u662f\u65bc240BC\uff0c\u4e0d\u96e2\u4e9e\u6b77\u5c71\u5927\u57ce\u4e00\u6b65\uff0c\u800c\u80fd\u65bc\u4e00\u5c0f\u6642\u5167\uff0c\u5c31\u4ee5\u5be6\u9a57\u8b49\u660e\u4e86\u5730\u7403\u662f\u5713\u5f62\u7684\uff0c\u4ee5\u53ca\u8a08\u7b97\u4e86\u5730\u7403\u7684\u5713\u5468\u3002<\/strong>
\"ar\"<\/a>
\u4ed6\u6240\u4f7f\u7528\u7684\u65b9\u6cd5\u76f8\u7576\u7c21\u55ae:<\/strong>
1. \u4ee5\u4e00\u6839\u516b\u5c3a\u9577\u7684\u5713\u68cd\uff0c\u5728”\u590f\u81f3 (summer solstice)”\u6642\uff0c\u8c4e\u7acb\u5728\u4e9e\u6b77\u5c71\u5927\u57ce (Alexandria) \u3002\u65bc\u6b63\u5348\u6642\uff0c\u7531\u5b83\u7684\u9670\u5f71\u53ca\u68cd\u5b50\u7684\u9577\u5ea6\uff0c\u4ed6\u91cf\u51fa\u592a\u967d\u8207\u5730\u5e73\u9762\u7684”\u4ef0\u89d2”(elevation angle\uff0c a ) \u70ba7\u00b012’\u3002<\/strong><\/p>\n

2. \u4e8b\u5148\u77e5\u9053\u963f\u65af\u65fa\u57ce (Aswan\uff0c\u53e4\u7a31Syene) \u662f\u5728\u4e9e\u6b77\u5c71\u5927\u57ce\u7684\u6b63\u5357\u65b9 (\u898b\u5730\u5716) [\u5373\u5ef6\u8457\u5730\u7403\u7684\u540c\u4e00\u5357\u5317\u7684\u5b50\u5348\u7dda (meridian)] (\u8a3b: \u4f9d\u8fd1\u4ee3\u592a\u7a7a\u6e2c\u5716\uff0c\u9019\u53ea\u662f\u5927\u7565\u6b63\u78ba\u7684\u5047\u8a2d\u3002)\uff0c\u4ee5\u53ca\u5169\u57ce\u4e4b\u9593\u7684\u8ddd\u96e2\u3002<\/strong><\/p>\n

3. \u4e8b\u5148\u77e5\u9053 \u963f\u65af\u65fa\u57ce \u4f4d\u65bc\u5317\u56de\u6b78\u7dda (Tropic of Cancer) \u4e0a\u3002[\u5373\u5728”\u590f\u81f3”\u6b63\u5348\u6642\uff0c\u592a\u967d\u5728\u963f\u65af\u65fa\u57ce\u7684\u6b63\u4e0a\u65b9 (a = 0\u00b0)]\u3002<\/strong>
\"shadow\"<\/a> \"fig1\"<\/a> \"fig2\"<\/a><\/p>\n

\u7d50\u8ad6:<\/span> <\/strong>
\u7531\u4e0a\u9762\u6e2c\u91cf\u7d50\u679c\uff0c\u6211\u5011\u53ef\u5f97\u5230\u4e0b\u9762\u7684\u7d50\u8ad6:<\/strong>
1. \u7531\u65bc\u5728\u4e9e\u6b77\u5c71\u5927\u57ce \u53ca\u963f\u65af\u65fa\u57ce\uff0c\u6240\u6e2c\u592a\u967d\u7684\u4ef0\u89d2”a”\u4e0d\u540c\uff0c\u56e0\u800c\u63a8\u77e5\u5730\u7403\u4e0d\u662f\u5e73\u7684 (flat)\uff0c\u800c\u662f\u5713\u5f62\u7684 (round)\u3002<\/strong><\/p>\n

2. \u5047\u8a2d\u5730\u7403\u662f\u5713\u7684\uff0c\u4ee5\u7c21\u55ae\u7684\u5713\u5f62\u5e7e\u4f55\uff0c\u6211\u5011\u53ef\u4ee5\u4e0b\u9762\u516c\u5f0f\u8a08\u7b97\u5730\u7403\u7684\u5713\u5468\u3002\"fig5\"<\/a>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/strong>
\u56e0\u7da0\u8272\u7684<\/strong>\u5f27\u9577 (arc length) D (<\/strong>\u4e9e\u6b77\u5c71\u5927\u57ce \u81f3\u963f\u65af\u65fa\u57ce\u4e4b\u9593\u7684\u8ddd\u96e2) <\/strong>\u662f\u5713\u5468\u9577\u7684 a\/360 \u5206\u4e4b\u4e00\uff0c\u56e0\u6b64\u5713\u5468\u9577\u662fD \u7684360\/a \u500d<\/strong>:<\/strong>
\u5730\u7403\u5713\u5468\u9577=\u00a0 360D\/a \u3002<\/strong><\/span>
\u53ea\u8981\u77e5\u9053\u5169\u57ce\u9593\u7684\u8ddd\u96e2(D)\uff0c\u53ca\u4ef0\u89d2(a)\uff0c\u5c31\u53ef\u8a08\u7b97\u51fa\u5730\u7403\u7684\u5713\u5468\u3002<\/span><\/strong><\/p>\n

\u7528\u4e0a\u9762\u516c\u5f0f\u8a08\u7b97\u5730\u7403\u5713\u5468\u7684\u6e96\u78ba\u6027\uff0c\u4e3b\u8981\u662f\u4f9d\u9760\u4e9e\u6b77\u5c71\u5927\u57ce \u81f3\u963f\u65af\u65fa\u57ce\u4e4b\u9593\u7684\u8ddd\u96e2\u4ee5\u53ca\u5169\u57ce\u662f\u5728\u540c\u4e00\u5b50\u5348\u7dda\u4e0a\u5169\u500b\u5047\u8a2d\u3002\u5982\u4ee5\u57c3\u53ca\u4eba\u7576\u6642\u6240\u77e5, D = 925 \u516c\u91cc\uff0c\u52a0\u4e0a\u6240\u6e2c\u77e5\u7684\u4ef0\u89d2\uff0ca = 7\u00b012\u2032= 7.2\u00b0,\u00a0\u4ee3\u5165\u4e0a\u9762\u516c\u5f0f\uff0c\u6211\u5011\u5f88\u5bb9\u6613\u7b97\u51fa:<\/strong>
\u5730\u7403\u5713\u5468= 45,931 \u516c\u91cc\u3002<\/strong><\/p>\n

\u73fe\u4ee3\u9ad8\u79d1\u6280\u7684\u6e2c\u91cf\u662f: \u5730\u7403\u5357\u5317\u65b9\u5411\u5468\u9577\u662f 40,008 \u516c\u91cc\u3002(\u5ef6\u8d64\u9053\u6771\u897f\u7684\u5713\u5468\u9577\u662f 40,075\u516c\u91cc)\u3002<\/strong><\/p>\n

<\u5169\u8005\u4e4b\u9593\u670914.8%\u7684\u8aa4\u5dee\u3002\u6b64\u5dee\u7570\u7684\u4e3b\u8981\u539f\u56e0\u662f\u7531\u65bc\u65bc\u4e0b\u9762\u56e0\u7d20: (1) \u53e4\u57c3\u53ca\u7576\u6642\u6e2c\u91cf\u7684\u5f9e\u4e9e\u6b77\u5c71\u5927\u57ce \u81f3\u963f\u65af\u65fa\u57ce\u9593\u7684\u8ddd\u96e2(D)\u4e0d\u6e96\u78ba\uff0c(2) \u5169\u57ce\u53ea\u662f\u5927\u7d04\u5728\u540c\u4e00\u5b50\u5348\u7dda\u4e0a\uff0c(3) \u5730\u7403\u662f\u6a62\u5713\u5f62 (ellipse) \u3002<\/strong><\/p>\n

\u5982\u679c\u4ee5\u73fe\u4ee3\u7684\u6e2c\u91cf\uff0c\u5169\u57ce\u9593\u7684\u8ddd\u96e2 D = 842.7 \u516c\u91cc\uff0c\u6211\u5011\u53ef\u5f97\u5230 “\u57c3\u62c9\u6258\u8272\u5c3c”\u6240\u6e2c\u7684\u5730\u7403\u5713\u5468\u61c9\u662f 41,844\u516c\u91cc\u3002\u9019\u7b54\u6848\u5c31\u53ea\u67094.6% \u7684\u8aa4\u5dee\uff0c\u771f\u4e0d\u932f(not bad for one day’s work) \u3002<\/strong><\/p>\n

\u4e0d\u7ba1\u5982\u4f55\uff0c\u57c3\u62c9\u6258\u8272\u5c3c(Eratosthenes) \u5728\u5169\u5343\u591a\u5e74\u524d\uff0c\u5c31\u6709\u6b63\u78ba\u7684\u79d1\u5b78\u89c0\u5ff5\u3002\u9019\u8b49\u660e\u53e4\u4eba\u8ddf\u73fe\u4ee3\u4eba\u4e00\u6a23\u8070\u660e\u3002\u667a\u6167\u662f\u4eba\u985e\u5929\u751f\u7684\u672c\u8cea\uff0c\u4e0d\u662f\u9032\u5316\u4f86\u7684\u3002<\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

How Ancient Greek Showed that Earth is Round, And Measured Earth’s Circumference within one hour? \u00a0\u00a0 \u4fe1\u5805\u00a0 10\/7\/2013 \u00a0\u00a0 \u524d\u8a00: \u4fe1\u5805\u5728\u6b64\u7e7c\u7e8c\u89e3\u8aaa “\u65e5\u4e2d\u7acb\u8289\u6e2c\u5f71”\u7684\u5999\u7528\u3002\u4e0a\u6587\u63d0\u53ca\u4e2d\u570b\u7684\u8001\u7956\u5b97\uff0c\u7528\u4e00\u6839\u516b\u5c3a\u9577\u7684\u5713\u68cd\uff0c\u6e2c\u77e5\u4e00\u5e74\u6709365.25\u5929\uff0c\u5283\u51fa\u4e86\u4e8c\u5341\u56db\u500b\u7bc0\u6c23\u5faa\u74b0\uff0c\u53ca\u756b\u51fa\u592a\u6975\u9670\u967d\u5716\u3002(\u8acb\u770b \u592a\u6975\u9670\u967d\u5716\u7684\u7531\u4f86) \u6b64\u6587\u89e3\u8aaa\u5e7e\u5343\u5e74\u524d\uff0c\u53e4\u5e0c\u81d8\u4eba\uff0c\u4e5f\u662f”\u65e5\u4e2d\u7acb\u8289\u6e2c\u5f71”\uff0c\u65bc\u4e00\u5c0f\u6642\u5167\uff0c\u8b49\u660e\u4e86\u5730\u7403\u662f\u5713\u5f62\u7684 (round)\uff0c\u4e26\u4e14\u4e08\u91cf\u4e86\u5730\u7403\u7684\u5713\u5468 (Earth circumference)\u3002<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1,49],"tags":[],"class_list":["post-1841","post","type-post","status-publish","format-standard","hentry","category-1","category-49"],"_links":{"self":[{"href":"https:\/\/www.worldofmastermind.com\/index.php?rest_route=\/wp\/v2\/posts\/1841","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.worldofmastermind.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.worldofmastermind.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.worldofmastermind.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.worldofmastermind.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1841"}],"version-history":[{"count":74,"href":"https:\/\/www.worldofmastermind.com\/index.php?rest_route=\/wp\/v2\/posts\/1841\/revisions"}],"predecessor-version":[{"id":7929,"href":"https:\/\/www.worldofmastermind.com\/index.php?rest_route=\/wp\/v2\/posts\/1841\/revisions\/7929"}],"wp:attachment":[{"href":"https:\/\/www.worldofmastermind.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1841"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.worldofmastermind.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1841"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.worldofmastermind.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1841"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}