{"common":{"save":0,"post_id":"8529","level":2,"total":10,"point":10,"point_extra":0},"segment":[{"id":"7793","mon_id":"1158790","chapter_id":"1158796","post_id":"8529","question":"<p>L\u1ef1c có tác d\u1ee5ng làm cho v\u1eadt r\u1eafn quay quanh m\u1ed9t tr\u1ee5c khi<\/p>","options":["<strong>A.<\/strong> l\u1ef1c có giá n\u1eb1m trong m\u1eb7t ph\u1eb3ng vuông góc v\u1edbi tr\u1ee5c quay và c\u1eaft tr\u1ee5c quay.","<strong>B.<\/strong> l\u1ef1c có giá n\u1eb1m trong m\u1eb7t ph\u1eb3ng vuông góc v\u1edbi tr\u1ee5c quay và không c\u1eaft tr\u1ee5c quay.","<strong>C.<\/strong> l\u1ef1c có giá c\u1eaft tr\u1ee5c quay.","<strong>D.<\/strong> l\u1ef1c có giá song song v\u1edbi tr\u1ee5c quay."],"correct":"2","level":"2","hint":"","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>B.<\/strong> l\u1ef1c có giá n\u1eb1m trong m\u1eb7t ph\u1eb3ng vuông góc v\u1edbi tr\u1ee5c quay và không c\u1eaft tr\u1ee5c quay.<\/span><\/p><p>L\u1ef1c có tác d\u1ee5ng làm cho v\u1eadt r\u1eafn quay quanh m\u1ed9t tr\u1ee5c khi l\u1ef1c có giá n\u1eb1m trong m\u1eb7t ph\u1eb3ng vuông góc v\u1edbi tr\u1ee5c quay và không c\u1eaft tr\u1ee5c quay.<\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2025-02-28 08:37:10","option_type":"txt","len":3},{"id":"7794","mon_id":"1158790","chapter_id":"1158796","post_id":"8529","question":"<p>Moment l\u1ef1c c\u1ee7a m\u1ed9t l\u1ef1c \u0111\u1ed1i v\u1edbi tr\u1ee5c quay là bao nhiêu n\u1ebfu \u0111\u1ed9 l\u1edbn c\u1ee7a l\u1ef1c là<br \/>5 N và cánh tay \u0111òn là 2 mét?<\/p>","options":["<strong>A.<\/strong> 10 N","<strong>B.<\/strong> 10 Nm","<strong>C.<\/strong> 11 N","<strong>D.<\/strong> 11 Nm"],"correct":"2","level":"2","hint":"<p>Moment l\u1ef1c \u0111\u01b0\u1ee3c tính theo công th\u1ee9c: M = F.d (Nm).<\/p>","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>B.<\/strong> 10 Nm.<\/span><\/p><p>Moment l\u1ef1c c\u1ee7a m\u1ed9t l\u1ef1c \u0111\u1ed1i v\u1edbi tr\u1ee5c quay là: M = F . d = 5 . 2 = 10 Nm.<\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2025-02-28 08:39:31","option_type":"txt","len":0},{"id":"7795","mon_id":"1158790","chapter_id":"1158796","post_id":"8529","question":"<p>Khi m\u1ed9t v\u1eadt r\u1eafn quay quanh m\u1ed9t tr\u1ee5c thì t\u1ed5ng moment l\u1ef1c tác d\u1ee5ng lên v\u1eadt có giá tr\u1ecb<\/p>","options":["<strong>A.<\/strong> b\u1eb1ng không","<strong>B.<\/strong> luôn d\u01b0\u01a1ng","<strong>C.<\/strong> luôn âm","<strong>D.<\/strong> khác không"],"correct":"4","level":"2","hint":"","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>D.<\/strong> khác không.<\/span><\/p><p>\u0110\u1ea1i l\u01b0\u1ee3ng \u0111\u1eb7c tr\u01b0ng cho tác d\u1ee5ng làm quay c\u1ee7a m\u1ed9t l\u1ef1c là moment c\u1ee7a nó.<br \/>Moment M c\u1ee7a m\u1ed9t l\u1ef1c \u0111\u01b0\u1ee3c tính b\u1eb1ng tích \u0111\u1ed9 l\u1edbn c\u1ee7a l\u1ef1c v\u1edbi kho\u1ea3ng cách t\u1eeb tr\u1ee5c quay \u0111\u1ebfn \u0111\u01b0\u1eddng th\u1eb3ng trùng v\u1edbi ph\u01b0\u01a1ng c\u1ee7a l\u1ef1c (giá c\u1ee7a l\u1ef1c): M = F.d.<br \/>V\u1eady nên, khi v\u1eadt r\u1eafn quay, moment c\u1ee7a l\u1ef1c có giá tr\u1ecb khác 0.<\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2025-02-28 08:42:05","option_type":"txt","len":2}]}