水平面上A,B两个物体的质量分别为m1和m2,与水平面间的动摩擦因数均相同,A,B分别在水平力F1和F2的作用下,
\u4e24\u4e2a\u7269\u4f53\u7684\u8d28\u91cf\u5206\u522b\u4e3am1\u548cm2\uff0c\u4e14m1=4m2\uff0c\u5f53\u5b83\u4eec\u4ee5\u76f8\u540c\u7684\u52a8\u80fd\u5728\u52a8\u6469\u64e6\u56e0\u6570\u76f8\u540c\u7684\u6c34\u5e73\u9762\u4e0a\u8fd0\u884c\u65f6\uff0c\u5b83\u4eec\u7684\u6ed1\u56e0\u4e3a\u662f\u4e24\u7269\u4f53\u53ea\u53d7\u91cd\u529b\u548c\u6469\u64e6\u529b\uff0c\u6469\u64e6\u529b\u548c\u91cd\u529b\u6709\u5173\uff0c\u53ef\u4ee5\u5f97\u51fa\u6469\u64e6\u529bF\uff1d\u03bcM\u3002a=F/M
\u6240\u4ee5\u53ef\u77e5a\u4e0e\u7269\u4f53\u8d28\u91cf\u65e0\u5173\u3002a=\u03bc\u3002\u4ee5\u76f8\u540c\u52a8\u91cf\u53731/2(m1)(v1)\u5e73\u65b9\uff1d1/2(m2)(v2)\u5e73\u65b9
\u6240\u4ee5\u53ef\u5f97\u51fa\uff08v1)\uff1a(v2)\uff1d1\uff1a2\uff0c\u6839\u636ev=v0+at\u5f97\u51fa(t1)\uff1a(t2)\uff1d1\uff1a2
\u53c8\u56e0\u4e3as=(v0)t+1/2at\u5e73\u65b9\u3002\u6240\u4ee5\u5f97\u51fa(s1)\uff1a(s2)\uff1d1\uff1a4
\u7ed3\u679c\u9009\u62e9D
C \u7531\u529f\u7684\u5b9a\u4e49\u5f0f\uff1a W = Fl cos \u03b8 \u53ef\u77e5\uff0c\u4e24\u79cd\u60c5\u51b5\u4e0b\u529b\u76f8\u540c\uff0c\u4f4d\u79fb\u76f8\u540c\uff0c\u529b\u548c\u4f4d\u79fb\u7684\u5939\u89d2\u4e5f\u76f8\u540c\uff0c\u6240\u4ee5 W 1 = W 2 \uff0cC\u6b63\u786e\u3002
设A B物体向右匀加速运动A物体受B物体的支持力N和摩擦力f
N=m1g
F1-f=m1a
AB做为一个整体:
F1+F2-u(m1+m2)g=(m1+m2)a
解出: f=F1-m1a=(m2F1-m1F2)/(m1+m2)+um1g
绛旓細绛旀鏄細25/6 瑙ｉ鍒嗘瀽锛欶A+FB=12,璇存槑2鐗╀綋鍦ㄥ垎绂诲墠锛岀殑鍔犻熷害鏄亽瀹氫笉鍙樼殑 a=4/3 璁続鍜孊涔嬮棿鐨勪綔鐢ㄥ姏涓篎锛屽垯鏈塅A-F=3a 寰 F=5-2t杩欐槸AB涓ょ墿浣涔嬮棿浣滅敤鍔涖備笅闈㈡垜浠濊冧笅AB浠涔堟椂鍊欏紑濮嬪垎绂汇傚湪鍒嗙鍓嶏紝AB鍔犻熷害鍜岄熷害鏄竴鏍风殑锛屽湪鍒嗙鐨勭灛闂达紝AB涔嬮棿娌℃湁浣滅敤鍔涖傛湁浜轰細瀵硅繖涓骇鐢...
绛旓細10+2*1-2*0.1*10=10N 閭ｄ箞璺濈灏15+锛10/500锛*100=17cm
绛旓細A銆b涓璧疯繍鍔ㄧ殑锛岄鍏堜綔涓轰竴涓暣浣撴潵鐪嬶紝鎺ㄥ姏 F 鎵鍙楁懇鎿﹀姏涓 F1=渭锛坢1+m2锛塯 姘村钩鏂瑰悜鍚堝姏涓篎2=F-F1=F-渭锛坢1+m2锛塯 璁惧姞閫熷害涓篴 鏈塅2=锛坢1+m2锛塧 a=锛團-渭锛坢1+m2锛塯锛/锛坢1+m2锛夎鐗╀綋闂翠綔鐢ㄥ姏涓篎3 瀵鐗╀綋B锛鏈 F3-渭m2g=m2a 鍙緱F3=m2a+渭m2g=m2*F/锛坢1...
绛旓細璁 A 杩愬姩鏃堕棿涓 t 2 锛岃 B 涓 A 鐩哥寮濮嬭繍鍔ㄦ椂闂翠负 t 1 锛屼互 A 銆 B 缁勬垚绯荤粺涓虹爺绌跺璞★紝鐢卞姩閲忓畾鐞嗘湁浠ヤ笅鍏崇郴寮- f A t 2 - f B t 1 =0- m A 蠀 A 锛 锛 f A = 渭m A g 锛- f B t 1 = 渭m B g ...
绛旓細V2 锛 鐢变簬A鐗╀綋鎬诲叡杩愬姩6s锛岀敱鍏紡 V1 = V0 -a*t 鍙畻鍑虹鎾炲墠杩愬姩 t=1s銆備簬鏄緱鐭ョ鎾炲悗A鐗╀綋鍐嶆杩愬姩 5s銆傛湁鍏紡 V2 = a* t 锛堝叕寮--3锛夊緱鐭 V2 = 5 m/s 甯﹀叆鍏紡2 绠楀嚭Vb = 8m/s 纰版挒鍚嶢 B鐗╀綋鍒嗙锛屾墍浠ュ崟鐙彧鍙楀埌鎽╂摝闃诲姏锛屽姞閫熷害閮芥槸1m/s^2. 鍙湅浣淏鐗╀綋浠8m...
绛旓細鐗╁潡B浣滃寑閫熺洿绾胯繍鍔,鏁呮墍鍙楀悎澶栧姏涓0;姘村钩鏂瑰悜.涓婄墿鍧桝瀵B鐨浣滅敤鍔汧ab,妗岄潰瀵笲鐨勬懇鎿﹀姏骞宠 鏈:Fab = u*mb*g = 0.5*2*10 =10(M)鐗╁潡B瀵A鐨浣滅敤鍔涗笌鐗╁潡A瀵笲鐨勪綔鐢ㄥ姏浜掍负浣滅敤鍔涗笌鍙嶄綔鐢ㄥ姏,鍥犳:Fba =Fab =10(N)璁句汉瀵圭墿鍧桝鐨勪綔鐢ㄥ姏澶у皬涓篎,A浣滃寑閫熺洿绾胯繍鍔,鍥犳姘村钩鏂瑰悜涓庡瀭鐩存柟鍚戝悎...
绛旓細鍏夋粦姘村钩闈娌℃湁鎽╂摝鍔涳紝鎵浠鏀跺埌鐨勫姏鏄疢1*a,浣滅敤鍔涗笌鍙嶄綔鐢ㄥ姏锛孉瀵B鐨浣滅敤鍔涗篃鏄繖涓俛=f/锛坢1+m2锛夋墍浠ヤ綔鐢ㄥ姏涓簃1*F/(m1+m2)
绛旓細x= 1 2 a t 2 = 1 2 脳 4 3 脳2锛 5 2 m= 25 6 m 绛旓細锛1锛変粠t=0鍒癆銆B鑴辩鍓嶏紝瀹冧滑鐨勫姞閫熷害鏄 4 3 m/s 2 锛涳紙2锛変粠t=0鍒癆銆丅鑴辩鏃锛岀墿浣揂鐨浣嶇Щ鏄 25 6 m 锛
绛旓細鎾ら櫎鎷夊姏鍚庝袱鐗╀綋鐨閫熷害鍥捐薄骞宠锛屾晠鍔犻熷害澶у皬鐩哥瓑锛屽嵆a1=a2=渭g=1m/s2鎵浠ノ1=渭2=0.1锛庢晠A姝ｇ‘锛庤嫢m1=m2锛屽垯f1=f2锛屾牴鎹姩鑳藉畾鐞嗗a鏈塛F1-f1s1=0鍚岀悊瀵b鏈塛F2-f2s2=0鈭祍1=4脳2.5脳12=5.0ms2=2脳5脳12=5.0m鈭碬F1=WF2锛鏁B閿欒锛庤嫢F1=F2瀵逛簬m1鍒欐湁F1-渭1m1g=m1a1瑙ｅ緱...
绛旓細C 璇曢鍒嗘瀽:鐢卞姩鑳藉畾鐞嗭細 锛屽彲鐭ユ挙鍘诲姏鏃朵簩鑰呮湁鐩稿悓鐨勫姩鑳锛屼袱鐗╀綋鍙戠敓纰版挒鍓嶇殑鍔ㄩ噺 锛屽彲寰楀姩閲 锛岀鎾炲悗锛堝彇鍚戝彸涓烘鏂瑰悜锛夌敱鍔ㄩ噺瀹堟亽瀹氬緥锛 锛屽垯 鏂瑰悜鍚戝彸銆傛晠閫塁銆
