C1.<\/strong> ( trang 102 sgk V\u1eadt L\u00fd 10): H\u00e3y vi\u1ebft quy t\u1eafc momen l\u1ef1c cho chi\u1ebfc cu\u1ed1c chim khi c\u00e2n b\u1eb1ng (H\u00ecnh 18.2).<\/p>\n\n\n\n Tr\u1ea3 l\u1eddi:<\/strong><\/ins><\/p>\n\n\n\n Khi chi\u1ebfc cu\u1ed1c c\u00e2n b\u1eb1ng v\u1edbi tr\u1ee5c quay O<\/p>\n\n\n\n Ta c\u00f3: F1<\/sub>d1<\/sub> = F2<\/sub>d2<\/sub>.<\/p>\n\n\n\n B\u00e0i 3 (trang 103 SGK V\u1eadt L\u00fd 10) :<\/strong> H\u00e3y v\u1eadn d\u1ee5ng qui t\u1eafc momen l\u1ef1c v\u00e0o c\u00e1c tr\u01b0\u1eddng h\u1ee3p sau:<\/p>\n\n\n\n a)\tM\u1ed9t ng\u01b0\u1eddi d\u00f9ng x\u00e0 beng \u0111\u1ec3 b\u1ea9y m\u1ed9t h\u00f2n \u0111\u00e1 (H\u00ecnh 18.3).<\/p>\n\n\n\n