鎬ユ眰涓閬撳垵涓暟瀛﹂鐨勭瓟妗堬紒锛

璁惧湴闈㈠崐寰勪负r锛屽垯鐩寸绉熷緞涓2r锛岄珮涓2r
鍦嗗敜鐬庣伓鏌卞绉=搴曢潰绉楅珮=蟺r²*2r=2蟺r³=8
r=涓夋鏍瑰彿涓嬶紙4/蟺锛夌背鍜屾壆

璁捐繑瑁わ細楂榟=搴曞紛闆归潰鐩村緞d=x绫
瀹圭НV=蟺*锛坉/2)^2*h
=蟺*x^3/4=8
=> x=(32/蟺)鏍瑰彿3
鈮2.1677绫
鍗婂緞r=x/2=(4/蟺锛夋牴鍙风涓栧竼3
鈮1.084

璁鹃珮锛堝嵆鐩村緞锛変负2x锛屽垯鍗婂緞涓簒
2x脳x²脳蟺=8
寰楋紝婧愯x=涓夋鏍瑰彿涓嬶紙4/蟺锛

绛旓細搴曢潰鍗婂緞涓轰笁娆℃牴鍙蜂笅锛4/蟺锛塵銆
锛堥浌鎮夐棴濡傛灉瑕佺害鐨勯檰棣栬瘽锛寈鈮0.0323锛夛紙璁＄畻鍣ㄧ畻鐨勶紝淇濈暀浜嗗嚑涓湁鏁堟暟瀛楋紝蟺鍙栦簡3.14锛

璁惧渾绋挎灟鏌辩殑搴曢潰鍗婂緞涓簉绫筹紝閿殏娲炲垯鐩寸墿绔栧緞涓2r绫筹紝楂樹负2r绫
鍦嗘煴瀹圭Н=搴曢潰绉楅珮=蟺r²*2r=2蟺r³=8
r=涓夋鏍瑰彿涓嬶紙4/蟺锛=1/蟺涓夋鏍瑰彿锛4蟺²锛夌背

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浣犵湅涓涓嬪惂锛屾竻娓告鎼滃湪鎴戠浉鍐岀瓟鍜岄攢閲岋紝鏈夎繃绋嬨 鎴戝啓鍦ㄧ焊涓婄収涓嬫潵浜嗭紝鐢ㄦ墦瀛楀お鎱紝鍐欑殑璇濇瘮杈冩竻妤氥 浣犲彲浠ュ彟瀛樹负锛屾斁澶х湅銆

瀹规暚鎵扮Н=8 瀹圭Н=搴曢潰x楂樺垽姗 璁鹃珮涓簒锛屽嵆搴曢潰鐩村緞涓簒 鍥(x/2)骞虫柟X鍦嗗懆鐜嘪 x=8
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