{"segment":[{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"M\u1ed9t v\u1eadt dao \u0111\u1ed9ng c\u00e0ng nhanh th\u00ec \u00e2m ph\u00e1t ra c\u00e0ng:","select":["A. Tr\u1ea7m.","B. B\u1ed5ng.","C. Vang.","D. Truy\u1ec1n \u0111i xa."],"hint":"","explain":"<span class='basic_left'>Dao \u0111\u1ed9ng c\u00e0ng nhanh th\u00ec t\u1ea7n s\u1ed1 c\u00e0ng l\u1edbn, \u00e2m ph\u00e1t ra c\u00e0ng cao ( c\u00e0ng b\u1ed5ng ) khi t\u1ea7n s\u1ed1 dao \u0111\u1ed9ng c\u00e0ng l\u1edbn. <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> ","column":2}]}],"id_ques":2231},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":"T\u1ea7n s\u1ed1 l\u00e0 g\u00ec:","select":["A. S\u1ed1 dao \u0111\u1ed9ng trong m\u1ed9t gi\u00e2y.","B. S\u1ed1 gi\u00e2y th\u1ef1c hi\u1ec7n m\u1ed9t dao \u0111\u1ed9ng.","C. \u0110\u1ed9 l\u1edbn c\u1ee7a dao \u0111\u1ed9ng.","D. \u0110\u1ed9 to c\u1ee7a \u00e2m thanh."],"hint":"","explain":"<span class='basic_left'>T\u1ea7n s\u1ed1 l\u00e0 s\u1ed1 dao \u0111\u1ed9ng trong m\u1ed9t gi\u00e2y.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span> ","column":2}]}],"id_ques":2232},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":"Chu k\u00ec l\u00e0 g\u00ec?","select":["A. S\u1ed1 gi\u00e2y \u0111\u1ec3 th\u1ef1c hi\u1ec7n hai dao \u0111\u1ed9ng.","B. S\u1ed1 dao \u0111\u1ed9ng trong m\u1ed9t gi\u00e2y.","C. S\u1ed1 gi\u00e2y \u0111\u1ec3 th\u1ef1c hi\u1ec7n m\u1ed9t dao \u0111\u1ed9ng.","D. \u0110\u1ed9 l\u1edbn c\u1ee7a \u00e2m thanh."],"hint":"","explain":"<span class='basic_left'>Chu k\u00ec l\u00e0 s\u1ed1 gi\u00e2y \u0111\u1ec3 th\u1ef1c hi\u1ec7n m\u1ed9t dao \u0111\u1ed9ng.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> ","column":1}]}],"id_ques":2233},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":"\u0110\u01a1n v\u1ecb c\u1ee7a t\u1ea7n s\u1ed1 l\u00e0 g\u00ec?","select":["A. Jun","B. Gi\u00e2y","C. M\u00e9t","D. H\u00e9c"],"hint":"","explain":"<span class='basic_left'>\u0110\u01a1n v\u1ecb c\u1ee7a t\u1ea7n s\u1ed1 l\u00e0 H\u00e9c (Hz).<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span><\/span> ","column":2}]}],"id_ques":2234},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":"T\u1ea7n s\u1ed1 dao \u0111\u1ed9ng c\u00e0ng nh\u1ecf th\u00ec \u00e2m c\u00e0ng:","select":["A. Tr\u1ea7m","B. Cao","C. B\u1ed5ng","D. Vang"],"hint":"","explain":"<span class='basic_left'>T\u1ea7n s\u1ed1 dao \u0111\u1ed9ng c\u00e0ng nh\u1ecf th\u00ec \u00e2m c\u00e0ng tr\u1ea7m.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span> ","column":2}]}],"id_ques":2235},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":"K\u00ed hi\u1ec7u c\u1ee7a t\u1ea7n s\u1ed1 v\u00e0 \u0111\u01a1n v\u1ecb c\u1ee7a t\u1ea7n s\u1ed1 l\u00e0 g\u00ec?","select":["A. K\u00ed hi\u1ec7u t\u1ea7n s\u1ed1 l\u00e0 f \u0111\u01a1n v\u1ecb l\u00e0 m.","B. K\u00ed hi\u1ec7u t\u1ea7n s\u1ed1 l\u00e0 T \u0111\u01a1n v\u1ecb l\u00e0 s.","C. K\u00ed hi\u1ec7u t\u1ea7n s\u1ed1 l\u00e0 f \u0111\u01a1n v\u1ecb l\u00e0 Hz.","D. K\u00ed hi\u1ec7u t\u1ea7n s\u1ed1 l\u00e0 f \u0111\u01a1n v\u1ecb l\u00e0 s."],"hint":"","explain":"<span class='basic_left'>K\u00ed hi\u1ec7u t\u1ea7n s\u1ed1 l\u00e0 f \u0111\u01a1n v\u1ecb l\u00e0 Hz.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> ","column":2}]}],"id_ques":2236},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"Hai v\u1eadt dao \u0111\u1ed9ng, v\u1eadt 1 dao \u0111\u1ed9ng v\u1edbi t\u1ea7n s\u1ed1 40Hz, v\u1eadt 2 dao \u0111\u1ed9ng v\u1edbi t\u1ea7n s\u1ed1 60Hz.Cho\u0323n c\u00e2u tra\u0309 l\u01a1\u0300i \u0111u\u0301ng? ","select":["A. V\u1eadt 1 dao \u0111\u1ed9ng nhanh h\u01a1n v\u1eadt 2.","B. V\u1eadt 2 ph\u00e1t ra \u00e2m cao h\u01a1n v\u1eadt 1.","C. V\u1eadt 1 ph\u00e1t ra \u00e2m cao h\u01a1n v\u1eadt 2.","D. Ca\u0301c c\u00e2u tra\u0309 l\u01a1\u0300i A,B,C \u0111\u00ea\u0300u \u0111u\u0301ng."],"hint":"","explain":"<span class='basic_left'>\u00c2m ph\u00e1t ra c\u00e0ng cao khi t\u1ea7n s\u1ed1 dao \u0111\u1ed9ng c\u00e0ng l\u1edbn.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> ","column":1}]}],"id_ques":2237},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":"V\u1eadt ph\u00e1t ra \u00e2m cao h\u01a1n khi n\u00e0o?","select":["A. Khi v\u1eadt dao \u0111\u1ed9ng m\u1ea1nh h\u01a1n.","B. Khi v\u1eadt dao \u0111\u1ed9ng ch\u1eadm h\u01a1n.","C. Khi v\u1eadt dao \u0111\u1ed9ng nhanh h\u01a1n.","D. Khi v\u1eadt l\u1ec7ch ra kh\u1ecfi v\u1ecb tr\u00ed c\u00e2n b\u1eb1ng nhi\u1ec1u h\u01a1n."],"hint":"","explain":"<span class='basic_left'>V\u1eadt dao \u0111\u1ed9ng nhanh h\u01a1n => c\u00f3 t\u1ea7n s\u1ed1 l\u1edbn h\u01a1n => ph\u00e1t ra \u00e2m cao h\u01a1n.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> ","column":1}]}],"id_ques":2238},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":"M\u1ed9t v\u1eadt trong 5s th\u00ec th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c 20 dao \u0111\u1ed9ng h\u1ecfi t\u1ea7n s\u1ed1 c\u1ee7a v\u1eadt l\u00e0 bao nhi\u00eau?","select":["A. 4 Hz","B. 2 Hz","C. 20 Hz","D. 0,25 Hz"],"hint":"","explain":"<span class='basic_left'>Trong 5s th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c 20 dao \u0111\u1ed9ng, v\u1eady trong 1s th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c: $\\dfrac{20}{5}=4$ dao \u0111\u1ed9ng. <br\/>V\u1eady f = 4Hz.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span> ","column":2}]}],"id_ques":2239},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"V\u1eadt 1 th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c 10 dao \u0111\u1ed9ng trong 2s, v\u1eadt 2 th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c 5 dao \u0111\u1ed9ng trong 2s, ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang:","select":["A. v\u1eadt 1 dao \u0111\u1ed9ng ch\u1eadm h\u01a1n v\u1eadt 2","B. v\u1eadt 1 c\u00f3 t\u1ea7n s\u1ed1 l\u1edbn h\u01a1n v\u1eadt 2","C. v\u1eadt 2 c\u00f3 t\u1ea7n s\u1ed1 b\u1eb1ng v\u1eadt 1","D. T\u1ea5t c\u1ea3 \u0111\u1ec1u sai"],"hint":"","explain":"<span class='basic_left'>V\u1eadt 1 th\u1ef1c hi\u1ec7n 10 dao \u0111\u1ed9ng trong 2s, n\u00ean trong 1s v\u1eadt 1 th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c 5 dao \u0111\u1ed9ng.<br\/> V\u1eady ${{f}_{1}}$ = 5Hz.<br\/>V\u1eadt 2 th\u1ef1c hi\u1ec7n 5 dao \u0111\u1ed9ng trong 2s, n\u00ean trong 1s v\u1eadt 2 th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c 2,5 dao \u0111\u1ed9ng.<br\/> V\u1eady ${{f}_{2}}$ = 2,5Hz.<br\/> V\u1eadt 1 c\u00f3 t\u1ea7n s\u1ed1 l\u1edbn h\u01a1n v\u1eadt 2.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> ","column":2}]}],"id_ques":2240},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":"Tai ng\u01b0\u1eddi b\u00ecnh th\u01b0\u1eddng c\u00f3 th\u1ec3 nghe \u0111\u01b0\u1ee3c nh\u1eefng \u00e2m trong kho\u1ea3ng t\u1ea7n s\u1ed1 l\u00e0 bao nhi\u00eau:","select":["A. 10 Hz t\u1edbi 20 Hz","B. 20000 Hz t\u1edbi 40000 Hz","C. 20 Hz t\u1edbi 20000 Hz","D. Tr\u00ean 100000 Hz"],"hint":"","explain":"<span class='basic_left'>Tai ng\u01b0\u1eddi b\u00ecnh th\u01b0\u1eddng c\u00f3 th\u1ec3 nghe \u0111\u01b0\u1ee3c nh\u1eefng \u00e2m trong kho\u1ea3ng t\u1ea7n s\u1ed1 t\u1eeb 20 Hz t\u1edbi 20000 Hz.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> ","column":2}]}],"id_ques":2241},{"time":24,"part":[{"title":"","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":"Ch\u1ecdn \u0111\u00e1p \u00e1n sai:","select":["A. \u00c2m \u0110\u1ed3 c\u00f3 t\u1ea7n s\u1ed1 dao \u0111\u1ed9ng nh\u1ecf h\u01a1n \u00e2m \u0110\u1ed1.","B. \u00c2m R\u00ea th\u1ea5p h\u01a1n \u00e2m Mi.","C. \u00c2m La t\u1ea7n s\u1ed1 dao \u0111\u1ed9ng cao h\u01a1n \u00e2m Pha.","D. \u00c2m Son c\u00f3 t\u1ea7n s\u1ed1 dao \u0111\u1ed9ng th\u1ea5p h\u01a1n \u00e2m R\u00ea."],"hint":"","explain":"<span class='basic_left'>T\u1ea7n s\u1ed1 dao \u0111\u1ed9ng c\u1ee7a \u00e2m cao l\u1edbn h\u1edbn t\u1ea7n s\u1ed1 dao \u0111\u1ed9ng c\u1ee7a \u00e2m th\u1ea5p. T\u1ea7n s\u1ed1 dao \u0111\u1ed9ng c\u1ee7a \u00e2m R\u00ea nh\u1ecf h\u01a1n t\u1ea7n s\u1ed1 dao \u0111\u1ed9ng c\u1ee7a \u00e2m Son.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span><\/span> ","column":1}]}],"id_ques":2242},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"Khi n\u00e0o ta n\u00f3i ph\u00e1t ra \u00e2m tr\u1ea7m:","select":["A. Khi \u00e2m nghe to.","B. Khi \u00e2m ph\u00e1t ra v\u1edbi t\u1ea7n s\u1ed1 th\u1ea5p.","C. Khi \u00e2m nghe nh\u1ecf.","D. Khi \u00e2m ph\u00e1t ra v\u1edbi t\u1ea7n s\u1ed1 cao."],"hint":"","explain":"<span class='basic_left'>\u00c2m ph\u00e1t ra c\u00e0ng tr\u1ea7m khi t\u1ea7n s\u1ed1 dao \u0111\u1ed9ng c\u00e0ng nh\u1ecf.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> ","column":2}]}],"id_ques":2243},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":"Th\u1ebf n\u00e0o l\u00e0 si\u00eau \u00e2m :","select":["A. L\u00e0 nh\u1eefng \u00e2m c\u00f3 t\u1ea7n s\u1ed1 n\u1eb1m trong kho\u1ea3ng 20Hz t\u1edbi 20000 Hz.","B. Nh\u1eefng \u00e2m con ng\u01b0\u1eddi kh\u00f4ng nghe th\u1ea5y \u0111\u01b0\u1ee3c.","C. Nh\u1eefng \u00e2m nghe ti\u1ebfng to. ","D. Nh\u1eefng \u00e2m c\u00f3 t\u1ea7n s\u1ed1 l\u1edbn h\u01a1n 20000Hz."],"hint":"","explain":"<span class='basic_left'>Si\u00eau \u00e2m l\u00e0 nh\u1eefng \u00e2m c\u00f3 t\u1ea7n s\u1ed1 l\u1edbn h\u01a1n 20000Hz.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span><\/span> ","column":1}]}],"id_ques":2244},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":"Th\u1ebf n\u00e0o l\u00e0 h\u1ea1 \u00e2m: ","select":["A. Nh\u1eefng ti\u1ebfng n\u00f3i th\u00ec th\u1ea7m.","B. Nh\u1eefng \u00e2m c\u00f3 t\u1ea7n s\u1ed1 t\u1eeb 40 Hz t\u1edbi 100 Hz.","C. Nh\u1eefng \u00e2m c\u00f3 t\u1ea7n s\u1ed1 nh\u1ecf h\u01a1n 20 Hz.","D. Nh\u1eefng \u00e2m c\u00f3 t\u1ea7n s\u1ed1 nh\u1ecf h\u01a1n 10 Hz."],"hint":"","explain":"<span class='basic_left'>H\u1ea1 \u00e2m l\u00e0 nh\u1eefng \u00e2m c\u00f3 t\u1ea7n s\u1ed1 nh\u1ecf h\u01a1n 20 Hz.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> ","column":1}]}],"id_ques":2245},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"K\u00e9o l\u1ec7ch m\u1ed9t con l\u1eafc d\u00e2y v\u00e0 bu\u00f4ng nh\u1eb9 cho dao \u0111\u1ed9ng. Khi \u0111\u00f3 ta kh\u00f4ng nghe th\u1ea5y \u00e2m ph\u00e1t ra v\u00ec:","select":["A. Con l\u1eafc kh\u00f4ng ph\u1ea3i l\u00e0 ngu\u1ed3n \u00e2m","B. Con l\u1eafc dao \u0111\u1ed9ng v\u1edbi t\u1ea7n s\u1ed1 b\u00e9","C. Con l\u1eafc dao \u0111\u1ed9ng v\u1edbi t\u1ea7n s\u1ed1 qu\u00e1 cao","D. Chi\u1ec1u d\u00e0i con l\u1eafc dao \u0111\u1ed9ng ng\u1eafn"],"hint":"","explain":"<span class='basic_left'>Tai ng\u01b0\u1eddi ch\u1ec9 nghe \u0111\u01b0\u1ee3c nh\u1eefng \u00e2m thanh c\u00f3 t\u1ea7n s\u1ed1 t\u1eeb 20Hz t\u1edbi 20000 Hz. Con l\u1eafc dao \u0111\u1ed9ng v\u1edbi t\u1ea7n s\u1ed1 b\u00e9 n\u00ean ta kh\u00f4ng nghe \u0111\u01b0\u1ee3c \u00e2m ph\u00e1t ra.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> ","column":2}]}],"id_ques":2246},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"Con l\u1eafc dao \u0111\u1ed9ng v\u1edbi t\u1ea7n s\u1ed1 10 Hz, \u0111\u1ec3 th\u1ef1c hi\u1ec7n 1 dao \u0111\u1ed9ng con l\u1eafc c\u1ea7n:","select":["A. 1s","B. 0,1s","C. 0,2s","D. 10s"],"hint":"","explain":"<span class='basic_left'>f = 10Hz => trong 1s th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c 10 dao \u0111\u1ed9ng. N\u00ean 1 dao \u0111\u1ed9ng th\u1ef1c hi\u1ec7n trong $\\dfrac{1}{10}=0,1s$ <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> ","column":2}]}],"id_ques":2247},{"time":24,"part":[{"title":"","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":"V\u1eadt 1 th\u1ef1c hi\u1ec7n 1 dao \u0111\u1ed9ng trong 0.2s, v\u1eadt 2 th\u1ef1c hi\u1ec7n 1 dao \u0111\u1ed9ng trong 0.5s.<br\/>Ch\u1ecdn \u0111\u00e1p \u00e1n sai:","select":["A. V\u1eadt 1 c\u00f3 t\u1ea7n s\u1ed1 5Hz.","B. V\u1eadt 2 c\u00f3 t\u1ea7n s\u1ed1 2Hz.","C. V\u1eadt 1 dao \u0111\u1ed9ng nhanh h\u01a1n v\u1eadt 2.","D. V\u1eadt 1 ph\u00e1t ra \u00e2m tr\u1ea7m h\u01a1n v\u1eadt 2."],"hint":"","explain":"<span class='basic_left'>V\u1eadt 1 th\u1ef1c hi\u1ec7n 1 dao \u0111\u1ed9ng trong 0.2s => ${{f}_{1}}$ = $\\dfrac{1}{0,2}=5Hz$.<br\/>V\u1eadt 2 th\u1ef1c hi\u1ec7n 1 dao \u0111\u1ed9ng trong 0.5s => ${{f}_{2}}$ = $\\dfrac{1}{0,5}=2Hz$ .<br\/> => ${{f}_{1}}$ > ${{f}_{2}}$ n\u00ean v\u1eadt 1 dao \u0111\u1ed9ng nhanh h\u01a1n v\u00e0 ph\u00e1t ra \u00e2m cao h\u01a1n v\u1eadt 2.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span><\/span> ","column":2}]}],"id_ques":2248},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":"Con mu\u1ed7i ph\u00e1t ra \u00e2m cao h\u01a1n con ong \u0111\u1ea5t do:","select":["A. Con mu\u1ed7i v\u1ed7 c\u00e1nh nhanh h\u01a1n con ong \u0111\u1ea5t.","B. Con ong \u0111\u1ea5t to h\u01a1n con mu\u1ed7i.","C. Con mu\u1ed7i v\u1ed7 c\u00e1nh \u00edt h\u01a1n con ong \u0111\u1ea5t.","D. Con ong \u0111\u1ea5t n\u1eb7ng h\u01a1n con mu\u1ed7i."],"hint":"","explain":"<span class='basic_left'>Con v\u1eadt n\u00e0o v\u1ed7 c\u00e1nh nhanh h\u01a1n th\u00ec t\u1ea7n s\u1ed1 l\u1edbn h\u01a1n cho n\u00ean ph\u00e1t ra \u00e2m cao h\u01a1n.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span> ","column":1}]}],"id_ques":2249},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":"V\u1eadt n\u00e0o sau \u0111\u00e2y ph\u00e1t ra \u00e2m cao nh\u1ea5t:","select":["A. Trong 1s d\u00e2y \u0111\u00e0n th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c 100 dao \u0111\u1ed9ng. ","B. Trong 1 ph\u00fat con l\u1eafc th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c 3000 dao \u0111\u1ed9ng.","C. Trong 10s, m\u1eaft tr\u1ed1ng th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c 600 dao \u0111\u1ed9ng.","D. Trong 5s, con mu\u1ed7i v\u1ed7 c\u00e1nh \u0111\u01b0\u1ee3c 15 l\u1ea7n."],"hint":"","explain":"<span class='basic_left'>Trong 1s d\u00e2y \u0111\u00e0n th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c 100 dao \u0111\u1ed9ng => ${{f}_{1}}$ = 100 Hz.<br\/>Trong 1 ph\u00fat, con l\u1eafc th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c 3000 dao \u0111\u1ed9ng => ${{f}_{2}}$ = $\\dfrac{3000}{60}=50$ Hz.<br\/> Trong 10s, m\u1eb7t tr\u1ed1ng th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c 600 dao \u0111\u1ed9ng, => ${{f}_{3}}$ = $\\dfrac{600}{10}=60$ Hz.<br\/>Trong 5s, con mu\u1ed7i v\u1ed7 c\u00e1nh \u0111\u01b0\u1ee3c 15 l\u1ea7n.=> ${{f}_{4}}$ = $\\dfrac{15}{5}=3$ Hz. <br\/>V\u1eady ${{f}_{1}}$ l\u1edbn nh\u1ea5t. <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span> ","column":1}]}],"id_ques":2250}],"lesson":{"save":0,"level":2}}