1.质量为50kg的小丽，在体育课上进行爬杆训练，当她沿竖直杆匀速下滑时，杆对手的摩擦力的大小为＿
\u8d28\u91cf\u4e3a50kg\u7684\u5c0f\u5b87\uff0c\u5728\u4f53\u80b2\u8bfe\u4e0a\u8fdb\u884c\u722c\u6746\u8bad\u7ec3\uff0c\u5f53\u4ed6\u6cbf\u7ad6\u76f4\u6746\u5300\u901f\u4e0b\u6ed1\u65f6\uff0c\u6746\u5bf9\u624b\u7684\u6469\u64e6\u529b\u7684\u5927\u5c0f\u4e3a______N\uff0c\u5c0f\u5b87\u7684\u91cd\u529b\uff1aG=mg=50kg\u00d710N/kg=500N\uff1b\u5c0f\u5b87\u53d7\u5230\u7ad6\u76f4\u5411\u4e0b\u7684\u91cd\u529b\u548c\u7ad6\u76f4\u5411\u4e0a\u7684\u6469\u64e6\u529b\u4f5c\u7528\uff0c\u5e76\u4e14\u91cd\u529b\u548c\u6469\u64e6\u529b\u662f\u4e00\u5bf9\u5e73\u8861\u529b\uff0c\u56e0\u6b64\u6469\u64e6\u529b\u5927\u5c0f\u7b49\u4e8e\u5c0f\u5b87\u7684\u91cd\u529b\uff0c\u5927\u5c0f\u4e3a500N\uff0e\u6545\u7b54\u6848\u4e3a 500\uff0c\u7ad6\u76f4\u5411\u4e0a\uff0e
\u5c0f\u5b87\u7684\u91cd\u529b\uff1aG=mg=50kg\u00d710N/kg=500N\uff1b\u5c0f\u5b87\u53d7\u5230\u7ad6\u76f4\u5411\u4e0b\u7684\u91cd\u529b\u548c\u7ad6\u76f4\u5411\u4e0a\u7684\u6469\u64e6\u529b\u4f5c\u7528\uff0c\u5e76\u4e14\u91cd\u529b\u548c\u6469\u64e6\u529b\u662f\u4e00\u5bf9\u5e73\u8861\u529b\uff0c\u56e0\u6b64\u6469\u64e6\u529b\u5927\u5c0f\u7b49\u4e8e\u5c0f\u5b87\u7684\u91cd\u529b\uff0c\u5927\u5c0f\u4e3a500N\uff0e\u6545\u7b54\u6848\u4e3a 500\uff0c\u7ad6\u76f4\u5411\u4e0a\uff0e
1.竖直匀速运动摩擦力等于重力且方向和运动方向相反所以为500N（G=mg）方向为向上。
2.（1）P=W/t=FV=6N*0.1m/s=6w
（2）η=W有/W总*100%=6w/（10N*0.1m/s）=60%
1、看地理位置，赤道和南北极下降速度不同
绛旓細1.绔栫洿鍖閫熻繍鍔ㄦ懇鎿﹀姏绛変簬閲嶅姏涓旀柟鍚戝拰杩愬姩鏂瑰悜鐩稿弽鎵浠ヤ负500N锛圙=mg锛夋柟鍚戜负鍚戜笂銆2.锛1锛塒=W/t=FV=6N*0.1m/s=6w 锛2锛壩=W鏈/W鎬*100%=6w/锛10N*0.1m/s锛=60
绛旓細锛1锛夋牴鎹鎰忓彲寰楋細f=0.2G=0.2mg=0.2脳50kg脳10N/kg=100N锛涘洜涓哄仛鍖閫熺洿绾胯繍鍔紝澶勪簬骞宠 鐘舵侊紝鐢卞钩琛℃潯浠跺緱锛欶=f=100N锛庯紙2锛夌墿浣撳湪姘村钩鏂瑰悜鍙楁媺鍔汧鈥=150N锛屾懇鎿﹀姏f=100N浣滅敤锛屽垯鐗╀綋鍙楀埌鐨勫悎鍔涳細F鍚=F鈥-f=150N-100N=50N锛屾柟鍚戜笌鎷夊姏鏂瑰悜鐩稿悓锛屽嵆姘村钩鍚戝彸锛涘仛鍔犻熻繍鍔紟锛3锛夋鍦...
绛旓細锛1锛夋牴鎹鎰忓彲寰楋細f=0.2g=0.2mg=0.2脳50kg脳10n/kg=100n锛涘洜涓哄仛鍖閫熺洿绾胯繍鍔紝澶勪簬骞宠 鐘舵侊紝鐢卞钩琛℃潯浠跺緱锛歠=f=100n锛庯紙2锛夌墿浣撳湪姘村钩鏂瑰悜鍙楁媺鍔沠鈥=150n锛屾懇鎿﹀姏f=100n浣滅敤锛屽垯鐗╀綋鍙楀埌鐨勫悎鍔涳細f鍚=f鈥-f=150n-100n=50n锛屾柟鍚戜笌鎷夊姏鏂瑰悜鐩稿悓锛屽嵆姘村钩鍚戝彸锛涘仛鍔犻熻繍鍔紟锛3锛夋鍦...
绛旓細锛1锛塆=mg=50kg脳10N/kg=500N锛涳紙2锛 F=G=500N锛汸= F S = 500N 0.04 m 2 =1.25脳10 4 Pa锛涚瓟锛氾紙1锛夊皬鐞嗗悓瀛︾殑閲嶅姏鏄500N锛涳紙2锛夊皬鐞嗗悓瀛﹀鍦伴潰鐨勫帇寮1.25脳10 4 Pa锛
绛旓細锛1锛夌墿浣撳湪鎷夊姏浣滅敤涓嬪湪姘村钩妗岄潰涓婂仛鍖閫熺洿绾胯繍鍔紝鎵浠ユ懇鎿﹀姏涓庢媺鍔汧鏄竴瀵瑰钩琛″姏锛巉=F=200N锛庡湪绔栫洿鏂瑰悜涓婏紝閲嶅姏鍜屾敮鎸佸姏鏄竴瀵瑰钩琛″姏锛庢墍浠ユ敮鎸佸姏F鈥=G=mg=50kg脳10N/kg=500N锛庢懇鎿﹀姏鐨勫ぇ灏忎笌鍘嬪姏澶у皬鍜屾帴瑙﹂潰鐨勭矖绯欑▼搴︽湁鍏筹紝涓庣墿浣撶殑杩愬姩閫熷害鏃犲叧锛屾墍浠ユ懇鎿﹀姏涓嶅彉锛庯紙2锛夊皬鐞冨彈鍒颁笁涓姏...
绛旓細鍔犻燂級杩愬姩 璇曢鍒嗘瀽锛氾紙1锛夋湪鍧楀湪姘村钩鏂瑰悜涓婂彈鎷夊姏F涓庢粦鍔ㄦ懇鎿﹀姏f=0.2G=0.2mg=0.2脳50kg脳10N/kg=100N鐨勪綔鐢紝鍋氬寑閫熺洿绾胯繍鍔紝澶勪簬骞宠 鐘舵侊紝鐢卞钩琛℃潯浠跺緱锛欶=f=100N锛 锛2锛夐熷害涓0.4m/s鏃讹紝鐗╀綋鍙楀埌鐨勬懇鎿﹀姏f=0.2G=0.2mg=0.2脳50kg脳100N/kg=100N 锛3锛夌墿浣撳湪姘村钩鏂瑰悜鍙...
绛旓細G=mg=500N锛 4cm=0.04m w=fs=0.04m脳500n=20j p=w梅t=20j脳120梅60s=40w
绛旓細锛1锛夋湪鍧楀湪姘村钩鏂瑰悜涓婂彈鎷夊姏F涓庢粦鍔ㄦ懇鎿﹀姏f=0.2G=0.2mg=0.2脳50kg脳9.8N/kg=98N鐨勪綔鐢紝鍋氬寑閫熺洿绾胯繍鍔紝澶勪簬骞宠 鐘舵侊紝鐢卞钩琛℃潯浠跺緱锛欶=f=98N锛涚瓟锛氭湪鍧楀彈鍒扮殑鎷夊姏澶у皬鏄98N锛庯紙2锛夐熷害涓0.4m/s鏃讹紝鐗╀綋鍙楀埌鐨勬懇鎿﹀姏f=0.2G=0.2mg=0.2脳50kg脳9.8N/kg=98N绛旓細鐗╀綋鍙楀埌鐨勬懇鎿﹀姏...
绛旓細锛1锛夊皬鐞嗙殑閲嶅姏涓篏=mg=50Kg脳10N/Kg=500N 锛2锛夊皬鐞嗗鍦伴潰鐨勫帇鍔涗负F=G=500N灏忕悊绔欑珛鏃惰剼涓庡湴闈㈢殑鎺ヨЕ闈㈢Н涓篠=0.05m2 灏忕悊瀵瑰湴闈㈢殑鍘嬪己涓簆=FS=500N0.05m2=10000Pa绛旓細锛1锛夊皬鐞嗙殑浣撻噸涓500N锛涳紙2锛夊皬鐞嗙珯绔嬫椂瀵瑰湴闈㈢殑鍘嬪己涓1脳104Pa锛
绛旓細锛1锛夋牴鎹鎰忓彲寰楋細f=0.2G=0.2mg=0.2脳50kg脳10N/kg=100N锛涘洜涓哄仛鍖閫熺洿绾胯繍鍔紝澶勪簬骞宠 鐘舵侊紝鐢卞钩琛℃潯浠跺緱锛欶=f=100N锛庯紙2锛夌墿浣撳湪姘村钩鏂瑰悜鍙楁媺鍔汧鈥=120N锛屾懇鎿﹀姏f=100N浣滅敤锛屽垯鐗╀綋鍙楀埌鐨勫悎鍔涳細F鍚=F-f=120N-100N=20N锛屾柟鍚戜笌鎷夊姏鏂瑰悜鐩稿悓锛屽嵆姘村钩鍚戝彸锛涳紙3锛夌墿浣撳彈鍒扮殑鍚堝姏涓嶄负...
