為何圓柱體的承受能力較其他立體高?急!!!!!!10分!!!

真正的解釋當然唔係好似網友好怕homework咁樣咁簡單，而是要用到second moment of area。

圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_01.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_02.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_03.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_04.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_05.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_06.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_07.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_08.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_09.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_10.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_11.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_12.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_13.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_14.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_15.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_16.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_17.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_18.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_19.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_20.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_21.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_22.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_23.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_24.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_25.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_26.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_27.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_28.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_29.jpg


圖片參考：http://i212.photobucket.com/albums/cc82/doraemonpaul/yahoo_knowledge/second_moment/second_moment_30.jpg

因為它沒有角。