{"common":{"save":0,"post_id":"8607","level":1,"total":10,"point":10,"point_extra":0},"segment":[{"id":"7924","mon_id":"1158790","chapter_id":"1159772","post_id":"8607","question":"<p>Công th\u1ee9c tính công c\u1ee7a m\u1ed9t l\u1ef1c là:<\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$A = F.d$<\/span>.","<strong>B.<\/strong> <span class=\"math-tex\">$ A = mgh$<\/span>.","<strong>C.<\/strong> <span class=\"math-tex\">$A = F.s.sin\u03b1$<\/span>.","D. <span class=\"math-tex\">$A=\\dfrac{1}{2}mv^2$<\/span>."],"correct":"1","level":"1","hint":"","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>A.<\/strong> <span class=\"math-tex\">$A = F.d$<\/span>.<\/span><\/p><p>Công c\u1ee7a l\u1ef1c \u0111\u01b0\u1ee3c xác \u0111\u1ecbnh b\u1eb1ng bi\u1ec3u th\u1ee9c: <span style=\"color:#16a085;\"><span class=\"math-tex\">$A = F.d$<\/span>.<\/span><\/p><p>Trong \u0111ó F là \u0111\u1ed9 l\u1edbn c\u1ee7a l\u1ef1c tác d\u1ee5ng (N); d là \u0111\u1ed9 d\u1ecbch chuy\u1ec3n theo ph\u01b0\u01a1ng c\u1ee7a l\u1ef1c (m).<\/p><p>N\u1ebfu ph\u01b0\u01a1ng c\u1ee7a l\u1ef1c h\u1ee3p v\u1edbi ph\u01b0\u01a1ng chuy\u1ec3n \u0111\u1ed9ng m\u1ed9t góc α và làm v\u1eadt d\u1ecbch chuy\u1ec3n m\u1ed9t quãng \u0111\u01b0\u1eddng s, thì d = s.cosα ⇒ A = F.s.cosα.<\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2025-03-16 13:58:18","option_type":"math","len":0},{"id":"7925","mon_id":"1158790","chapter_id":"1159772","post_id":"8607","question":"<p>Công là \u0111\u1ea1i l\u01b0\u1ee3ng<\/p>","options":["<strong>A.<\/strong> vô h\u01b0\u1edbng, có th\u1ec3 âm ho\u1eb7c d\u01b0\u01a1ng.","<strong>B.<\/strong> vô h\u01b0\u1edbng, có th\u1ec3 âm, d\u01b0\u01a1ng ho\u1eb7c b\u1eb1ng không.","<strong>C.<\/strong> véct\u01a1, có th\u1ec3 âm, d\u01b0\u01a1ng ho\u1eb7c b\u1eb1ng không.","<strong>D.<\/strong> véct\u01a1, có th\u1ec3 âm ho\u1eb7c d\u01b0\u01a1ng."],"correct":"2","level":"1","hint":"","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>B.<\/strong> vô h\u01b0\u1edbng, có th\u1ec3 âm, d\u01b0\u01a1ng ho\u1eb7c b\u1eb1ng không.<\/span><\/p><p>N\u1ebfu ph\u01b0\u01a1ng c\u1ee7a l\u1ef1c h\u1ee3p v\u1edbi ph\u01b0\u01a1ng chuy\u1ec3n \u0111\u1ed9ng m\u1ed9t góc α và làm v\u1eadt d\u1ecbch chuy\u1ec3n m\u1ed9t quãng \u0111\u01b0\u1eddng s, thì d=s.cosα.<\/p><p>⇒ Công c\u1ee7a l\u1ef1c \u0111\u01b0\u1ee3c xác \u0111\u1ecbnh: A = F.s.cosα.<\/p><p>⇒ A có th\u1ec3 âm, d\u01b0\u01a1ng ho\u1eb7c b\u1eb1ng 0.<\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2025-03-16 14:00:36","option_type":"txt","len":3},{"id":"7927","mon_id":"1158790","chapter_id":"1159772","post_id":"8607","question":"<p>\u0110\u01a1n v\u1ecb c\u1ee7a công là<\/p>","options":["<strong>A.<\/strong> K.","<strong>B.<\/strong> N.","<strong>C.<\/strong> m.","<strong>D.<\/strong> J."],"correct":"4","level":"1","hint":"","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>D.<\/strong> J.<\/span><\/p><p>\u0110\u01a1n v\u1ecb c\u1ee7a công là J.<\/p><p>A – \u0111\u01a1n v\u1ecb c\u1ee7a nhi\u1ec7t \u0111\u1ed9.<\/p><p>B – \u0111\u01a1n v\u1ecb c\u1ee7a l\u1ef1c.<\/p><p>D – \u0111\u01a1n v\u1ecb \u0111\u1ed9 dài.<\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2025-03-16 14:02:27","option_type":"txt","len":0}]}
