圆锥直径12厘米,高14厘米,求表面积。(坑啊,小学六年级的题。) 六年级数学题
\u5df2\u77e5\u76f4\u5f84=12\u5398\u7c73\u9ad8=14\u5398\u7c73\u6c42\u8fd9\u4e2a\u5706\u67f1\u7684\u8868\u9762\u79ef\u5706\u67f1\u7684\u8868\u9762\u79ef
=2\u03c0DxH/2+2\u03c0D²/4
= \u03c0DH+\u03c0D²/2
=\u03c0Dx\uff08H+D/2\uff09
=3.14x12x(14+6)
=3.14x240
=753.6\u5e73\u65b9\u5398\u7c73
1\u3001\u4e00\u4e2a\u5706\u9525\u4f53\u7684\u96f6\u4ef6\uff0c\u5e95\u9762\u79ef\u662f 19\u5e73\u65b9\u5398\u7c73 \uff0c\u9ad8\u662f12\u5398\u7c73\u3002\u8fd9\u4e2a\u96f6\u4ef6\u7684\u4f53\u79ef\u662f\u591a\u5c11\uff1f
19\u00d712\u00d71/3\uff1d76\u7acb\u65b9\u5398\u7c73
2\u3001\u4e00\u5806\u7164\u6210\u5706\u9525\u5f62\u3002\u5e95\u9762\u534a\u5f84\u662f1.5\u7c73\uff0c\u9ad8\u662f1.1\u7c73\u3002\u8fd9\u5806\u7164\u7684\u4f53\u79ef\u662f\u591a\u5c11\uff1f
1.5\u00d71.5\u00d73.14\u00d71.1\u00d71.3\uff1d2.5905\u7acb\u65b9\u7c73
\u5982\u679c\u6bcf\u7acb\u65b9\u7c73\u7684\u7164\u7ea6\u91cd1.4\u5428\uff0c\u8fd9\u5806\u7164\u7ea6\u6709\u591a\u5c11\u5428\uff1f\uff08\u5f97\u6570\u4fdd\u7559\u6574\u5428\u3002\uff09
1.4\u00d72.5905\u22484\u5428
3\u3001
\uff081\uff09\u4e00\u4e2a\u5706\u67f1\u76f4\u5f846\u5398\u7c73\uff0c\u9ad812\u5398\u7c73\u6c42\u8868\u9762\u79ef\u548c\u4f53\u79ef\u3002
\u8868\u9762\u79ef
6\u00d73.14\u00d712\uff0b\uff086\u00f72\uff09\u00d7\uff086\u00f72\uff09\u00d73.14\u00d72\uff1d282.6\u5e73\u65b9\u5398\u7c73
\u4f53\u79ef
\uff086\u00f72\uff09\u00d7\uff086\u00f72\uff09\u00d73.14\u00d712\uff1d339.12\u7acb\u65b9\u5398\u7c73
\uff082\uff09\u4e00\u4e2a\u957f\u65b9\u4f53\u957f15\u5398\u7c73\uff0c\u5bbd10\u5398\u7c73\uff0c\u9ad820\u5398\u7c73\u6c42\u8868\u9762\u79ef\u548c\u4f53\u79ef\u3002
\u8868\u9762\u79ef
\uff0815\u00d710\uff0b15\u00d720\uff0b10\u00d720\uff09\u00d72\uff1d1300\u5e73\u65b9\u5398\u7c73
\u4f53\u79ef
15\u00d710\u00d720\uff1d3000\u7acb\u65b9\u5398\u7c73
\uff083\uff09\uff09\u4e00\u4e2a\u5706\u67f1\u76f4\u5f8414\u5398\u7c73\uff0c\u9ad85\u5398\u7c73\u6c42\u8868\u9762\u79ef\u548c\u4f53\u79ef\u3002
\u8868\u9762\u79ef
14\u00d73.14\u00d75\uff0b\uff0814\u00f72\uff09\u00d7\uff0814\u00f72\uff09\u00d73.14\u00d72\uff1d527.52\u5e73\u65b9\u5398\u7c73
\u4f53\u79ef
\uff0814\u00f72\uff09\u00d7\uff0814\u00f72\uff09\u00d73.14\u00d75\uff1d769.3\u7acb\u65b9\u5398\u7c73
4\u3001\u4e00\u4e2a\u5706\u67f1\u5f62\u7cae\u56e4\uff0c\u4ece\u91cc\u9762\u91cf\u5f97\u91cc\u9762\u534a\u5f84\u662f1.5\u7c73\uff0c\u9ad82\u7c73\u3002\u5982\u679c\u6bcf\u7acb\u65b9\u7c73\u7389\u7c73\u7ea6\u91cd750\u5343\u514b\uff0c\u8fd9\u4e2a\u7cae\u56e4\u80fd\u88c5\u591a\u5c11\u5428\u7389\u7c73\uff1f
\u4f53\u79ef\u662f
1.5\u00d71.5\u00d73.14\u00d72\uff1d14.13\u7acb\u65b9\u7c73
\u8fd9\u4e2a\u7cae\u56e4\u80fd\u88c5\u7389\u7c73
14.13\u00d7750\uff1d10597.5\u5343\u514b\uff1d10.5975\u5428
5\u3001\u5b66\u6821\u8981\u5728\u6559\u5b66\u533a\u548c\u64cd\u573a\u4e4b\u95f4\u4fee\u4e00\u9053\u56f4\u5899\uff0c\u539f\u8ba1\u5212\u7528\u571f\u77f335\u7acb\u65b9\u7c73\u3002\u540e\u6765\u591a\u5f00\u4e86\u4e00\u4e2a\u6708\u4eae\u95e8\uff0c\u51cf\u5c11\u4e86\u571f\u77f3\u7684\u7528\u91cf\u3002\u73b0\u7528\u4e86\u591a\u5c11\u7acb\u65b9\u7c73\u571f\u77f3\uff1f
\uff1f\uff1f\uff1f\uff1f\uff1f\uff1f
\u6570\u636e\u4e0d\u5b8c\u6574
6\u3001\u4e24\u4e2a\u5e95\u9762\u79ef\u76f8\u7b49\u7684\u5706\u67f1\uff0c\u4e00\u4e2a\u9ad8\u4e3a405\u5206\u7c73\uff0c\u4f53\u79ef\u4e3a81\u7acb\u65b9\u5206\u7c73\u3002\u53e6\u4e00\u4e2a\u9ad8\u4e3a3\u5206\u7c73\uff0c\u5b83\u7684\u4f53\u79ef\u662f\u591a\u5c11\uff1f
\u5e95\u9762\u79ef\u662f
81\u00f7405\uff1d0.2\u5e73\u65b9\u5206\u7c73
\u53e6\u4e00\u4e2a\u7684\u4f53\u79ef\u662f
0.2\u00d73\uff1d0.6\u7acb\u65b9\u5206\u7c73
直径12厘米,得知半径6厘米,所以底面等于6的平方乘以π,即36π。
几何体的高为14cm,所以其侧面半径为14cm,14的平方乘以π,为196π,又侧面的面积为其半圆的面积,所以侧面的面积为196π乘以2分之1,即98π。
98π加36π,等于134π。
母线长l: l²=14²-6²=160
底面周长C=2*π*6=12π
表面积S=½l*C+πr²=½*√160*12π+36π=24√10 π (cm²
)
r:12÷2=6(cm)
3.14×6×6×14÷3=527.52(cm的立方)
希望可帮助您!!……
r:12÷2=6(cm)
3.14×6×6×14÷3=527.52
12/2=6厘米
3.14*6*6*28/3=1055.04立方厘米
绛旓細搴曢潰鍗婂緞锛12梅2=6锛鍘樼背锛夊簳闈㈢Н锛6²脳3.14=113.04锛堝钩鏂瑰帢绫筹級鑳借娌欏瓙锛113.04脳15脳1/3=565.2锛堢珛鏂瑰帢绫筹級
绛旓細1/3x(19/2)^2x3.14x14=1322.5
绛旓細3.14涔7涔7涔12闄3
绛旓細鏈澶х殑鍦嗛敟浣撲笌杩欎釜鍦嗘煴浣撳悓搴曠瓑楂橈紝鏍规嵁鍦嗛敟浣撶Н鍏紡锛屽畠鐨勪綋绉槸鍦嗘煴浣撶殑1/3锛屾墍浠ュ墛鍘婚儴鍒嗘槸鍦嗘煴鐨2/3銆傚渾鏌变綋绉細3.14*锛12/2锛*锛12/2锛*15=1695.6锛堢珛鏂鍘樼背锛夊渾閿ヤ綋绉細1695.6*2/3=1130.4锛堢珛鏂瑰帢绫筹級
绛旓細(10)涓涓渾鏌卞舰鏃犵洊鑼舵澂,搴曢潰鐩村緞涓8cm銆侀珮涓10cm,瀹冪殑琛ㄩ潰绉槸( )cm2銆 (11)涓娈靛渾鏌卞舰鏈ㄦ枡,搴曢潰绉槸78.5dm2,楂20cm,瀹冪殑浣撶Н鏄( )銆 (12)涓鍦嗘煴褰㈡煴瀛,鐢ㄧ怀缁曚竴鍛ㄧ害闀3.14m,楂樼害4m,鏌卞瓙鐨勪綋绉害( )m3銆 (13)涓涓簳闈㈢Н鏄6m2,楂5m鐨鍦嗛敟浣,瀹冪殑浣撶Н鏄( )m3銆 (14)绛夊簳绛夐珮鐨勫渾鏌变綋鍜屽渾...
绛旓細19/2=9.5cm 9.5*9.5*3.14*14*涓夊垎涔嬩竴 绾︾瓑浜1322.46绔嬫柟鍘樼背
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绛旓細璁惧簳闈㈢Н涓簒锛岄珮搴︿负h x*8=1/3*x*12+x*(h-12)4x=锛坔-12锛墄 4=h-12 h=16