{"common":{"save":0,"post_id":"8047","level":2,"total":10,"point":10,"point_extra":0},"segment":[{"id":"8678","post_id":"8047","mon_id":"1159533","chapter_id":"1159535","question":"<p>M\u1ed9t m&aacute;y b\u01a1m n\u01b0\u1edbc th\u1ef1c hi\u1ec7n c&ocirc;ng 6000 J trong th\u1eddi gian 20 gi&acirc;y. C&ocirc;ng su\u1ea5t c\u1ee7a m&aacute;y b\u01a1m l&agrave;:<\/p>","options":["A. 200 W","B. 180 W","C. 300 W","D. 250 W "],"correct":"3","level":"2","hint":"<p>&Aacute;p d\u1ee5ng c&ocirc;ng th\u1ee9c t&iacute;nh c&ocirc;ng su\u1ea5t: P =&nbsp;<span class=\"math-tex\">$\\frac{A}{t}$<\/span><\/p>","answer":"<p>\u0110&aacute;p &aacute;n C. 300W<\/p><p>L\u1eddi gi\u1ea3i:&nbsp;&Aacute;p d\u1ee5ng c&ocirc;ng th\u1ee9c t&iacute;nh c&ocirc;ng su\u1ea5t: P =&nbsp;<span class=\"math-tex\">$\\frac{A}{t}$<\/span>&nbsp;=&nbsp;<span class=\"math-tex\">$\\frac{6000}{20}$<\/span>&nbsp;= 300 (W)<\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"125","test":"0","date":"2024-11-17 17:10:22","option_type":"txt","len":0},{"id":"8679","post_id":"8047","mon_id":"1159533","chapter_id":"1159535","question":"<p>M\u1ed9t ng\u01b0\u1eddi k&eacute;o m\u1ed9t v\u1eadt n\u1eb7ng b\u1eb1ng l\u1ef1c 200 N tr&ecirc;n \u0111o\u1ea1n \u0111\u01b0\u1eddng d&agrave;i 5 m, nh\u01b0ng l\u1ef1c k&eacute;o h\u1ee3p v\u1edbi ph\u01b0\u01a1ng ngang g&oacute;c 60&deg;. C&ocirc;ng th\u1ef1c hi\u1ec7n l&agrave;:<\/p>","options":["A. 250 J","B. 300 J","C. 500 J","D. 600 J"],"correct":"3","level":"2","hint":"<p>&Aacute;p d\u1ee5ng c&ocirc;ng th\u1ee9c: A = F.s.cos&nbsp;&alpha;<\/p>","answer":"<p>\u0110&aacute;p &aacute;n C. 500 J<\/p><p>L\u1eddi gi\u1ea3i:&nbsp;A = F.s.cos&nbsp;&alpha; = 200.5.cos 60&deg; = 200.5.0,5 = 500 (J)<\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"125","test":"0","date":"2024-11-17 17:15:04","option_type":"txt","len":0},{"id":"8916","post_id":"8047","mon_id":"1159533","chapter_id":"1159535","question":"<p>M\u1ed9t v\u1eadt c&oacute; kh\u1ed1i l\u01b0\u1ee3ng 20 kg \u0111\u01b0\u1ee3c n&acirc;ng l&ecirc;n \u0111\u1ed9 cao 3&nbsp;m. Bi\u1ebft gia t\u1ed1c tr\u1ecdng tr\u01b0\u1eddng g=10&thinsp;m\/<span class=\"math-tex\">$s^2$<\/span>. C&ocirc;ng m&agrave; l\u1ef1c n&acirc;ng th\u1ef1c hi\u1ec7n l&agrave;:<\/p>","options":["A. 600 J","B. 200 J","C. 60 J","D. 6000 J"],"correct":"1","level":"2","hint":"<p>&Aacute;p d\u1ee5ng c&ocirc;ng th\u1ee9c t&iacute;nh c&ocirc;ng: A = mgh<\/p>","answer":"<p>\u0110&aacute;p &aacute;n: A<\/p><p>L\u1eddi gi\u1ea3i: C&ocirc;ng m&agrave; l\u1ef1c n&acirc;ng th\u1ef1c hi\u1ec7n: A = mgh = 20.10.3 = 600 J<\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"125","test":"0","date":"2024-11-29 11:50:30","option_type":"txt","len":0}]}