求圆的直径公式 知道圆的周长，怎么求直径是多少，公式
\u5706\u7684\u76f4\u5f84\u8ba1\u7b97\u516c\u5f0f\u5706\u7684\u76f4\u5f84=2\u00d7\u534a\u5f84
\u5706\u7684\u76f4\u5f84=\u5468\u957f\u00f7\u5706\u5468\u7387
\u6839\u636e\u9898\u76ee\u7ed9\u51fa\u7684\u6761\u4ef6\u6765\u8ba1\u7b97\uff0c\u4e0d\u540c\u7684\u6761\u4ef6\uff0c\u8ba1\u7b97\u65b9\u6cd5\u662f\u4e0d\u4e00\u6837\u7684\uff0c\u6bd4\u5982\u7ed9\u51fa\u5706\u7684\u5468\u957f\u6216\u8005\u7ed9\u51fa\u534a\u5f84\uff0c\u90fd\u53ef\u4ee5\u7b97\u51fa\u5706\u7684\u76f4\u5f84\u3002
\u62d3\u5c55\u8d44\u6599
\u76f4\u5f84\uff0c\u662f\u6307\u901a\u8fc7\u4e00\u5e73\u9762\u56fe\u5f62\u6216\u7acb\u4f53\uff08\u5982\u5706\u3001\u5706\u9525\u622a\u9762\u3001\u7403\u3001\u7acb\u65b9\u4f53\uff09\u4e2d\u5fc3\u5230\u8fb9\u4e0a\u4e24\u70b9\u95f4\u7684\u8ddd\u79bb\uff0c\u901a\u5e38\u7528\u5b57\u6bcd\u201cd\u201d\u8868\u793a\u3002\u8fde\u63a5\u5706\u5468\u4e0a\u4e24\u70b9\u5e76\u901a\u8fc7\u5706\u5fc3\u7684\u76f4\u7ebf\u79f0\u5706\u76f4\u5f84\uff0c\u8fde\u63a5\u7403\u9762\u4e0a\u4e24\u70b9\u5e76\u901a\u8fc7\u7403\u5fc3\u7684\u76f4\u7ebf\u79f0\u7403\u76f4\u5f84\u3002
1\u3001\u76f4\u5f84\u662f\u901a\u8fc7\u5706\u5fc3\u4e14\u4e24\u4e2a\u7aef\u70b9\u90fd\u5728\u5706\u4e0a\u4efb\u610f\u4e00\u70b9\u7684\u7ebf\u6bb5\uff0c.\u4e00\u822c\u7528\u5b57\u6bcdd\u8868\u793a\u3002
2\u3001\u76f4\u5f84\u6240\u5728\u7684\u76f4\u7ebf\u662f\u5706\u7684\u5bf9\u79f0\u8f74\u3002
3\u3001\u76f4\u5f84\u7684\u4e24\u4e2a\u7aef\u70b9\u5728\u5706\u4e0a\uff0c\u5706\u5fc3\u662f\u76f4\u5f84\u7684\u4e2d\u70b9\u3002\u76f4\u5f84\u5c06\u5706\u5206\u4e3a\u9762\u79ef\u76f8\u7b49\u7684\u4e24\u90e8\u5206,\u4e2d\u95f4\u7684\u7ebf\u6bb5\u5c31\u53eb\u76f4\u5f84\uff08\u6bcf\u4e00\u4e2a\u90e8\u5206\u6210\u4e3a\u4e00\u4e2a\u534a\u5706\uff09\u3002
\u5706\u7684\u5468\u957f\u516c\u5f0f\u4e3aC\uff08\u5468\u957f\uff09=2\u03c0r\uff08\u534a\u5f84\uff09\u6216\u8005C=\u03c0d\uff08\u76f4\u5f84\uff09\u3002\u56e0\u6b64\uff0c\u5706\u7684\u76f4\u5f84d=C\uff08\u5468\u957f\uff09/\u03c0\u3002\u5176\u4e2d\u03c0\u662f\u5706\u5468\u7387\uff0c\u662f\u6709\u56fa\u5b9a\u6570\u503c\u7684\uff0c\u4e00\u822c\u53d6\u503c\u03c0=3.14\u3002
\u6269\u5c55\u8d44\u6599\uff1a\u5706\uff1a\u5706\u662f\u4e00\u79cd\u51e0\u4f55\u56fe\u5f62\u3002\u6839\u636e\u5b9a\u4e49\uff0c\u901a\u5e38\u7528\u5706\u89c4\u6765\u753b\u5706\u3002 \u540c\u5706\u5185\u5706\u7684\u76f4\u5f84\u3001\u534a\u5f84\u957f\u5ea6\u6c38\u8fdc\u76f8\u540c\uff0c\u5706\u6709\u65e0\u6570\u6761\u534a\u5f84\u548c\u65e0\u6570\u6761\u76f4\u5f84\u3002\u5706\u662f\u8f74\u5bf9\u79f0\u3001\u4e2d\u5fc3\u5bf9\u79f0\u56fe\u5f62\u3002\u5bf9\u79f0\u8f74\u662f\u76f4\u5f84\u6240\u5728\u7684\u76f4\u7ebf\u3002
\u534a\u5f84\uff1a\u8fde\u63a5\u5706\u5fc3\u548c\u5706\u4e0a\u7684\u4efb\u610f\u4e00\u70b9\u7684\u7ebf\u6bb5\u53eb\u505a\u534a\u5f84\uff0c\u5b57\u6bcd\u8868\u793a\u4e3ar\uff08radius\uff09
\u76f4\u5f84\uff1a\u901a\u8fc7\u5706\u5fc3\u5e76\u4e14\u4e24\u7aef\u90fd\u5728\u5706\u4e0a\u7684\u7ebf\u6bb5\u53eb\u505a\u76f4\u5f84\uff0c\u5b57\u6bcd\u8868\u793a\u4e3ad\uff08diameter\uff09\u3002\u76f4\u5f84\u6240\u5728\u7684\u76f4\u7ebf\u662f\u5706\u7684\u5bf9\u79f0\u8f74\u3002\u5706\u7684\u76f4\u5f84 d=2r
周长/π
S=πR(S周长，R为直径)得直径R=S/π
周长*半径/2
绛旓細鍦嗙殑鐩村緞=鍗婂緞脳2濡傛灉娌″憡璇夊崐寰勫憡璇変簡鍛ㄩ暱锛岄偅灏辩敤鍛ㄩ暱闄や互3.14
绛旓細鍦嗙殑鐩村緞鍏紡鏄細缁欏崐寰勬眰鍦嗙殑鐩村緞锛歞=2r锛涚粰鍛ㄩ暱姹傚渾鐨勭洿寰勶細d=c梅蟺銆傚彲浠ラ氳繃鍒诲害灏烘祴閲忋傞氳繃鍦嗗績杩炴帴鍦嗕笂鐨勪袱涓偣锛屾祴閲忎笁鐐瑰叡绾跨殑闀垮害銆傜洿寰勭殑鎬ц川锛1銆佸湪鍚屼竴涓渾涓洿寰勭殑闀垮害鏄崐寰勭殑2鍊嶏紝鍙互琛ㄧずd=2r鎴杛=d/2銆2銆佸湪鍚屼竴涓渾涓鸡闀夸负鍗婂緞2鍊嶇殑寮﹂兘鏄洿寰勩傚嵆鑻ョ嚎娈礵=2r锛宺鏄...
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绛旓細鍦嗙殑鐩村緞=2脳鍗婂緞銆傝В鏋愶細濡傛灉娌″憡璇夊崐寰勫憡璇変簡鍛ㄩ暱锛岄偅灏辩敤鍛ㄩ暱闄や互3.14銆傚彲閫氳繃闈㈢Н姹傚嚭鍗婂緞杩涜屾眰鍑虹洿寰勩傚渾鐨勭浉鍏冲欢浼革細鍦ㄥ悓涓骞抽潰鍐呭埌瀹氱偣鐨勮窛绂荤瓑浜庡畾闀跨殑鐐圭殑闆嗗悎鍙仛鍦嗚繖涓畾鐐瑰彨鍋氬渾鐨勫渾蹇冦傚渾褰竴鍛ㄧ殑闀垮害锛屽氨鏄渾鐨勫懆闀裤傝兘澶熼噸鍚堢殑涓や釜鍦嗗彨绛夊渾銆傚渾鏄竴涓n杈瑰舰锛坣涓烘棤闄愬ぇ鐨勬鏁存暟锛...
绛旓細1.鍦嗙殑鐩村緞=鍗婂緞脳2锛屽鏋滄病鍛婅瘔鍗婂緞鍛婅瘔浜嗗懆闀匡紝閭ｅ氨鐢ㄥ懆闀块櫎浠3.14銆傚彲閫氳繃闈㈢Н姹傚嚭鍗婂緞杩涜屾眰鍑虹洿寰勩2.鍦ㄤ竴涓钩闈㈠唴锛屼竴鍔ㄧ偣浠ヤ竴瀹氱偣涓轰腑蹇冿紝浠ヤ竴瀹氶暱搴︿负璺濈鏃嬭浆涓鍛ㄦ墍褰㈡垚鐨勫皝闂洸绾垮彨鍋氬渾銆3.鍦ㄥ悓涓骞抽潰鍐咃紝鍒板畾鐐圭殑璺濈绛変簬瀹氶暱鐨勭偣鐨勯泦鍚堝彨鍋氬渾銆傚渾鍙互琛ㄧず涓洪泦鍚坽M||MO|=r},鍦嗙殑鏍囧噯...
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