Transcription of 2018/7/3 力のモーメント（トルク）
1 2018/7/3 .. T L F sin N m .. T L F cos .. L.. F F. F sin F cos . O . O .. FB 1 FB 1. O O . FA FA . 3 FA FB FC 0 3 FA FB FC 0. FC FC. 1 FB 3 FC 0 1 FB 3 FC 0.. 2 N 4 N 8 N 2 N 4 N 8 N . 1 = 1 = 1 = -3 = -3 = -3 = O . O . O O.. FB 1 FB 1.. FA FA . 3 FA FB FC 0 3 FA FB FC 0. FC FC. 4 FC 1 FA 0 4 FC 1 FA 0.. 2 N 4 N 8 N 2 N 4 N 8 N . 0 = 0 0 = 0 0 = 0. 4 = 2 4 = 4 4 = 8. 1. 2018/7/3 . 18 19. A B .. 100 kg C . FA C A AC . TA LA FA sin A N m AB 2 . FB . TB LB FB sin B N m . FA( ).. TA TB N m FB( ). A=90 B=90 .. m=100kg 19 20. AB A . a 100 2a FC=0 (b=2a) B . C . Fc 102 N 50kgf BC 30 .. FA C.. FA = 102 102 BC .. P: . FA 103 N. A 30 . 150kgf . A B. m=100kg . 20 20. AB A AB A . B B . C C . BC 30 BC 30 .. C C.. x N T cos 30 0. sin 30 . BC y F T sin 30 W 0.. P: P: .. A 30 30 .. A A . B Tsin 30 0 B. 2 cos 30 . W 2T sin 30 0 . 2. 2018/7/3 . 20 20. AB A AB A . B B . C C.
2 BC 30 BC 30 .. 3 3 3. x N T cos 30 0 cos 30 x N T 0 cos 30 . 2 2 2 . y F T sin 30 W 0 1 1 1. sin 30 . y F T W 0 sin 30 . 2 2 2.. W 2T sin 30 0 1. W 2T 0. 2.. 20 . AB A . B . C . BC 30 .. 3. x N T 0 T W . 2. 1. y F T W 0 F . W.. 2 2. 3. N W . 1 2 . W 2T 0. 2.. G 0. O .. x1m1g+x2m2g+x3m3g=xG(m1+m2+m3)g .. XG. G.. O. x1m1+x2m2+x3m3 X1 m2g xG= X2 m3g m1+m2+m3. X3. m1g (m1+ m2+ m3)g 3. 2018/7/3 .. 2 m 2 m 2 m 2 m G 1 kg O G 1 kg 2 kg O 1 kg 2 kg 1 kg . 2 ( 2) 1 0 1 2 4 2 2 0 1 2 1 4 6. xG xG 2 1 1 4 2 1 1 4. x1m1+x2m2+x3m3 x1m1+x2m2+x3m3. xG= xG=. m1+m2+m3 m1+m2+m3.. aFa bFb cFc = 0. F = Fa Fb Fc Fa .. F.. a b Fb Fc c 4.
