如图,圆锥的下部是圆柱,圆柱的底面半径为4cm,母线长9cm,圆锥母线长5cm,求该几何体的表面积 (2013?南漳县模拟)已知,如图,圆锥的底面圆的半径为3c...
\u5982\u56fe\uff0c\u5706\u9525\u7684\u5e95\u9762\u534a\u5f84\u4e3a4cm\uff0c\u6bcd\u7ebf\u957f\u4e3a6cm\uff0c\u90a3\u4e48\u8fd9\u4e2a\u5706\u9525\u7684\u5168\u9762\u79ef\u662f______\uff0e\uff08\u7ed3\u679c\u4fdd\u7559\u03c0\u8fd9\u4e2a\u5706\u9525\u7684\u4fa7\u9762\u79ef=12?2\u03c0?4?6=24\u03c0\uff0c\u8fd9\u4e2a\u5706\u9525\u7684\u5e95\u9762\u5706\u7684\u9762\u79ef=\u03c0?42=16\u03c0\uff0c\u6240\u4ee5\u8fd9\u4e2a\u5706\u9525\u7684\u5168\u9762\u79ef=24\u03c0+16\u03c0=40\u03c0\uff08cm2\uff09\uff0e\u6545\u7b54\u6848\u4e3a40\u03c0cm2\uff0e
\u89e3\uff1a\u5706\u9525\u7684\u5e95\u9762\u5468\u957f\u662f6\u03c0\uff0c\u52196\u03c0=n\u03c0\u00d79180\u2234n=120\u00b0\uff0c\u5373\u5706\u9525\u4fa7\u9762\u5c55\u5f00\u56fe\u7684\u5706\u5fc3\u89d2\u662f120\u5ea6\uff0e\u2234\u2220APB=60\u00b0\u5219\u5728\u5706\u9525\u4fa7\u9762\u5c55\u5f00\u56fe\u4e2dAP=9\uff0cPC=4.5\uff0c\u2220ACP=90\u5ea6\uff0e\u2234\u5728\u5706\u9525\u4fa7\u9762\u5c55\u5f00\u56fe\u4e2dAC=AP2?PC2=923cm\uff0e\u6545\u7b54\u6848\u4e3a923cm\uff0e
表面积S=1/2(2∏RL)+2∏Rh=∏RL+2∏Rh=∏R(L+2h)=∏4×(5+2×9)=92∏平方厘米1/3*4*4*$*3+$*4*4*9=160$(立方厘米)
其中$为圆周率.
圆锥的高用勾股定理求的。5*5-4*4=3*3
1/3*4*4*$*3+$*4*4*9=160$
绛旓細琛ㄩ潰绉疭=1/2锛2鈭廟L锛+2鈭廟h=鈭廟L+2鈭廟h=鈭廟锛圠+2h锛=鈭4脳锛5+2脳9锛=92鈭忓钩鏂瑰帢绫
绛旓細鍥犱负锛鍦嗘煴鐨勫簳闈㈠懆闀挎槸12.56m 鎵浠ュ渾鏌辩殑搴曢潰鍗婂緞鏄2 V=V鍦嗘煴+V鍦嗛敟=蟺r^2*3+1/3蟺r^2*0.6=12蟺+1.2蟺=13.2蟺
绛旓細鍒嗘瀽锛氭湰棰樹腑鍦嗘煴銆佸渾閿ユ槸绛夊簳锛屼笉鍚岀殑鏄珮銆傛墍浠ヤ笉蹇呰冭檻搴曢潰绉紝鍙鑰冭檻楂樸鍦嗘煴浣鐨勯珮搴︽槸10鍘樼背锛屽鍣ㄥ唴鐨勬按楂7鍘樼背 銆傚緱鍑猴細姘寸殑浣撶Н=鍦嗘煴浣撶Н鐨7/10 绛夊簳绛夐珮鎯呭喌涓锛屽渾閿浣撶Н鏄渾鏌辩殑1/3锛岃屼笖棰樹腑鍦嗛敟浣鐨勯珮搴︽槸6鍘樼背锛屽渾鏌楂樺害鏄10鍘樼背锛屽緱鍑猴細鍦嗛敟浣撶Н=1/3脳鍦嗘煴浣撶Н鐨6/10=鍦嗘煴浣...
绛旓細浣撶Н =鍦嗛敟浣撶Н+鍦嗘煴浣撶Н =3鍒嗕箣1脳3.14脳2²脳1.5+3.14脳2²脳3 =43.96绔嬫柟绫
绛旓細濡傚浘
绛旓細3.14x锛18.84梅3.14梅2锛2x2=3.14*9/2=28.26/2=14.13(m³ 锛3.14*锛18.84梅3.14梅2锛2/3=3.14*9/3=28.26/3=9.42锛坢³ 锛夛紙14.13+9.42)*580=23.55*580锛1锛3.14x锛18.84梅3.14梅2锛2x2=3.14*9/2=28.26/2=14.13(m³ 锛3.14*锛18....
绛旓細鎶鍦嗘煴鍐呮按鐨勪綋绉垎鎴2閮ㄥ垎锛6鍘樼背楂樼殑姘寸殑浣撶Н涓庝笂闈㈠渾閿ョ瓑搴曠瓑楂橈紝鎵浠ュ渾鏌卞唴6鍘樼背楂樼殑姘寸殑浣撶Н鏄繖涓鍦嗛敟鐨浣撶Н鐨3鍊嶏紝6梅3=2锛堝帢绫筹級锛屽垯鎶婂渾鏌卞唴2鍘樼背楂樼殑姘村掑叆楂6鍘樼背鐨勫渾閿ュ鍣ㄥ唴鍗冲彲瑁呮弧锛屽垯鍦嗘煴鍐呮按杩樺墿涓7-2=5锛堝帢绫筹級锛6+5=11锛堝帢绫筹級锛岀瓟锛氫粠鍦嗛敟鐨勫皷鍒版恫闈㈢殑楂樻槸11鍘樼背锛...
绛旓細浠呴檺鍙傝:鍦嗛敟搴曢潰鐩村緞涓4锛屾埅闈负鐩磋涓夎褰紝鍒欏叾楂樹负2锛孷=鍏脳2(骞虫柟)脳2脳(1梅3) 6脳鍏脳2(骞虫柟)=80鍏/3
绛旓細鍦嗘煴鐨搴曢潰鍗婂緞锛6.28/3.14/2锛1绫 鍦嗘煴鐨勪綋绉紳3.14*1*1*1.5锛4.71绔嬫柟绫 鍦嗛敟鐨浣撶Н锛1/3*3.14*1*1*0.3锛0.314绔嬫柟绫 璋峰洡鐨勪綋绉紳鍦嗘煴鐨勪綋绉+鍦嗛敟鐨勪綋绉紳4.71+0.314锛5.024绔嬫柟绫
绛旓細浣跨敤骞虫粦杩囨浮鎺ュご杩炴帴鍦嗛敟浣鍜鍦嗘煴浣銆傚湪灏嗕笂閮ㄧ殑鍦嗛敟浣撳拰涓嬮儴鐨勫渾鏌变綋杩炴帴鏃讹紝鍏抽敭鏄‘淇濅袱鑰呬箣闂寸殑杩囨浮鏃㈠钩婊戝張缁撴瀯涓婄ǔ鍥恒傞氬父锛岃繖鍙互閫氳繃璁捐涓涓傚綋褰㈢姸鐨勮繃娓℃帴澶存潵瀹炵幇锛岃鎺ュご鍦ㄤ笂绔笌鍦嗛敟浣撶殑搴曡竟鐩稿尮閰嶏紝鍦ㄤ笅绔笌鍦嗘煴浣撶殑椤惰竟鐩搁傚簲銆傝繖绉嶈繃娓℃帴澶村彲鑳芥槸涓涓腑闂撮儴鍒嗭紝鍏跺舰鐘朵粠鍦嗛敟閫愭笎杩囨浮鍒...