数学书的外面贴一层塑料膜，数学书长20.5厘米，宽14.5厘米，厚是1里面，
\u4e00\u672c\u6570\u5b66\u8bfe\u672c\uff0c\u957f20.5\u5398\u7c73\uff0c\u5bbd14\u5398\u7c73\uff0c\u9ad81\u5398\u7c7320.5\u00d714=287\uff08\u5e73\u65b9\u5398\u7c73\uff09\uff0c20.5\u00d714\u00d71=287\uff08\u7acb\u65b9\u5398\u7c73\uff09\uff0c\u7b54\uff1a\u8fd9\u672c\u4e66\u5e73\u653e\u5728\u8bfe\u684c\u4e0a\uff0c\u5360\u53d6\u684c\u9762287\u5e73\u65b9\u5398\u7c73\uff0c\u5b83\u7684\u4f53\u79ef287\u7acb\u65b9\u5398\u7c73\uff0e
\u957f\u662f4.12cm
\u5bbd\u662f2.9cm
绛旓細鎵闇钖勮啘褰㈢姸涓轰竴鍦嗘煴浣撶殑渚ч潰绉殑涓鍗锛屽鍔犱竴涓渾鐨勯潰绉紙宸茬煡璇村叏灏侀棴鐨勮敩鑿滃ぇ妫氬槢锛夎绠楄繃绋嬪涓嬶細鍦嗘煴浣撲晶闈㈢Н鐨勪竴鍗婏紝瀹為檯涓婂氨鏄睍寮鍦嗘煴浣撲晶闈㈡墍褰㈡垚鐨勪竴涓煩褰 鍏堕潰绉负32*鍗婂渾褰㈢殑寮ч暱=32*(2pi)=64pi 娉ㄦ剰锛氱敤pi浠ｆ浛鍦嗗懆鐜囷紱鐭╁舰鐨勪竴杈逛负32锛屽彟涓杈瑰氨鏄渾鏌变綋搴曢潰鍦嗙殑鍗婂懆闀 濂戒簡锛岃繕鏈...
绛旓細鏍规嵁棰樻剰鍙互姹傚嚭濉戞枡钖勮啘妯埅闈㈢殑鐜舰闈㈢Н锛屽張鐭ラ亾濉戞枡钖勮啘鐨勯暱锛屾墍浠ュ彲浠ユ眰鍑哄鏂欒杽鑶滅殑浣撶Н鏉ワ紱濉戞枡钖勮啘灞曞紑鍚庢槸闈㈠緢澶э紝楂橀潪甯稿皬锛堝嵆钖勮啘鐨勫帤搴︼級鐨勯暱鏂逛綋锛岄暱鏂逛綋鐨勪綋绉拰楂樺凡鐭ワ紝浠ｅ叆鍏紡鍗冲彲姹傚嚭搴曢潰绉紟瑙ｏ細鐢遍鎰忕煡锛歋鐜=蟺锛圧2-r2锛=3.14脳銆(20/2 )鐨勫钩鏂-(8/2 )鐨勫钩鏂广=3.14...
绛旓細涓嶈繃锛屾瘡涓渾鐨勫崐寰勪笉涓鏍 鏈閲岄潰鐨勶紝鍗婂緞灏辨槸0.1姣背涔熷氨鏄1*10^-4m锛屾瘡澧炲姞涓涓湀锛屽帤搴﹀氨澧炲姞0.1姣背鐩村埌鏈澶栭潰鐨勫崐寰勬槸0.1m 閭ｆ渶閲岄潰鐨勫渾鍛ㄩ暱锛屼篃灏辨槸鎽婂紑鏉ョ殑闀垮害锛2*PAI*1*10^-4 锛圥AI鏄寚鍦嗗懆鐜囷級閲岄潰绗簩灞傚懆闀匡細2*PAI*锛1*10^-4*2锛 鏄寚鍘氬害鏄2涓钖勮啘锛涔熷氨鏄崐...
绛旓細4050梅28=144.64锛堝崈鍏嬶級濉戞枡鐨勫瘑搴︿负1g/銕3 144640/1=144640绔嬫柟鍘樼背 144640梅锛120x0.0125锛=96427鍘樼背=964.27绫
绛旓細鎶婂叿浣撴暟瀛椾唬鍏ワ紝鍙畻寰楄繖鍗疯杽鑶滅殑闀垮害涓5037345 cm锛岀害鏄5040 m銆傝嚦姝わ紝瀛︾敓灏变細鍙戠幇锛氳繖涔堥暱鐨勪竴鍗濉戞枡钖勮啘锛鐪熺殑灏嗗鏂欒杽鑶滃睍寮鏉ラ噺涔熸槸涓嶅鏄撳仛鍒扮殑锛屾兂瑕佺煡閬撳鏂欒杽鑶滄湁澶氶暱锛屽彧鏈変緷闈鏁板鐭ヨ瘑銆傝繖鏍凤紝鏁欏笀閫傚綋鍦板埄鐢ㄧ敓娲昏祫婧愶紝灏辨湁鏁堣鍙戜簡瀛︾敓鐨勫ソ濂囧績涓庡緛鏈嶆锛屾縺鍔变簡瀛︾敓瀛︿範骞跺埄鐢ㄦ暟瀛...
绛旓細闀✘瀹=闀挎柟褰㈢Ё鐢伴潰绉 瑙:璁捐繖鍗疯杽鎽稿睍寮鍚庢湁✘绫 1.5✘=30 鈥︹
绛旓細绗竴棰樺叾瀹炲氨鏄敤鍗婂渾鐨勫姬闀夸箻浠ユ婚暱搴﹀氨鏄〃闈㈢Н浜嗐傚崐鍦嗙殑寮ч暱=鍦嗗懆闀/2=3.14*4/2=6.28绫筹紝鎵浠ラ潰绉疭=鍗婂渾寮ч暱*鎬婚暱搴=6.28*15=94.2骞虫柟绫筹紝鎵浠ラ渶瑕濉戞枡钖勮啘94.2骞虫柟绫炽傜浜岄鍏堢畻鍑哄洓涓澂瀛愮殑鎬讳綋绉紝鐒跺悗璺熷彲涔愮殑鎬婚噺姣旇緝锛屽氨鍙互鐪嬪涓嶅浜嗐傛澂瀛愮殑鍗婂緞=6/2=3鍘樼背锛屾墍浠ユ澂瀛愮殑搴...
绛旓細瑕嗙洊鐨濉戞枡钖勮啘杩欎竴鏉′欢璇存槑浜嗚繖鍗婁釜鍦嗘煴鐨勪晶闈㈢Н鏄376.8骞虫柟绫筹紝鍙互鍋囪鏄竴涓渾鏌憋紝閭ｄ箞渚ч潰绉氨绛変簬376.8x2=753.6骞虫柟绫炽傛牴鎹袱娈垫槸3绫抽珮鐨勫崐鍦嗗舰鐮栧杩欎竴鏉′欢鍙互姹傚嚭杩欎釜鍦嗘煴鐨勫簳闈㈢Н3.14x3x2=18.84绫筹紝灏卞彲浠ユ眰鍑鸿繖涓渾鏌辩殑楂樻槸753.6/18.84=40绫炽傛眰鍑轰笂闈㈢殑鏉′欢鍚庯紝绗竴涓棶棰橈細...
绛旓細澶栧崐寰勶細26梅2=13锛堝帢绫筹級鍐呭崐寰勶細10梅2=5锛堝帢绫筹級渚ч潰绉槸锛氾紙13²-5²锛壝3.14=452.16锛堝钩鏂瑰帢绫筹級=45216锛堝钩鏂规绫筹級涓鍗锋湁锛45216梅0.3=150720锛堟绫筹級=150.72锛堢背锛夎兘閾猴細2脳150.72=301.44锛堝钩鏂圭背锛
绛旓細5鍘樼背锛0鍜5鍒诲害涔嬮棿鐨勯暱搴 6鍘樼背锛2鍜8鍒诲害涔嬮棿鐨勯暱搴 7鍘樼背锛2鍜9鍒诲害涔嬮棿鐨勯暱搴 8鍘樼背锛0鍜8鍒诲害涔嬮棿鐨勯暱搴 9鍘樼背锛0鍜9鍒诲害涔嬮棿鐨勯暱搴 鏃ュ父淇濇姢 1銆侀鍏堟槸灏哄瓙鐨勪娇鐢ㄦ柟娉曡姝ｇ‘锛屾瘮濡傜晫鍒掓潗鏂欑殑鏃跺欐渶濂戒笉瑕佷娇鐢濉戞枡灏哄瓙锛岃繖鏍蜂細寰堝鏄撹鍒姳鐨勩備篃鏈夊緢澶氱殑浜洪兘浼氱姱涓涓敊锛屽氨鏄湪鐢荤嚎鐨...
