{"segment":[{"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":"\u0110\u1ed9ng c\u01a1 n\u00e0o sau \u0111\u00e2y kh\u00f4ng ph\u1ea3i l\u00e0 \u0111\u1ed9ng c\u01a1 nhi\u1ec7t?","select":["A. \u0110\u1ed9ng c\u01a1 c\u1ee7a m\u00e1y bay ph\u1ea3n l\u1ef1c.","B. \u0110\u1ed9ng c\u01a1 c\u1ee7a xe m\u00e1y Hon-\u0111a.","C. \u0110\u1ed9ng c\u01a1 ch\u1ea1y m\u00e1y ph\u00e1t \u0111i\u1ec7n c\u1ee7a nh\u00e0 m\u00e1y th\u1ee7y \u0111i\u1ec7n S\u00f4ng \u0110\u00e0.","D. \u0110\u1ed9ng c\u01a1 ch\u1ea1y m\u00e1y ph\u00e1t \u0111i\u1ec7n c\u1ee7a nh\u00e0 m\u00e1y nhi\u1ec7t \u0111i\u1ec7n."],"hint":"","explain":"<span class='basic_left'>\u0110\u1ed9ng c\u01a1 ch\u1ea1y m\u00e1y ph\u00e1t \u0111i\u1ec7n c\u1ee7a nh\u00e0 m\u00e1y th\u1ee7y \u0111i\u1ec7n S\u00f4ng \u0110\u00e0 kh\u00f4ng ph\u1ea3i l\u00e0 \u0111\u1ed9ng c\u01a1 nhi\u1ec7t.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> ","column":1}]}],"id_ques":3000},{"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":"C\u00e2u n\u00e0o d\u01b0\u1edbi \u0111\u00e2y n\u00f3i \u0111\u00fang v\u1ec1 hi\u1ec7u su\u1ea5t c\u1ee7a \u0111\u1ed9ng c\u01a1 nhi\u1ec7t?","select":["A. Hi\u1ec7u su\u1ea5t cho bi\u1ebft \u0111\u1ed9ng c\u01a1 m\u1ea1nh hay y\u1ebfu.","B. Hi\u1ec7u su\u1ea5t cho bi\u1ebft \u0111\u1ed9ng c\u01a1 th\u1ef1c hi\u1ec7n c\u00f4ng nhanh hay ch\u1eadm.","C. Hi\u1ec7u su\u1ea5t cho bi\u1ebft nhi\u1ec7t l\u01b0\u1ee3ng t\u1ecfa ra khi 1 kg nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y ho\u00e0n to\u00e0n trong \u0111\u1ed9ng c\u01a1.","D. Hi\u1ec7u su\u1ea5t cho bi\u1ebft c\u00f3 bao nhi\u00eau ph\u1ea7n tr\u0103m nhi\u1ec7t l\u01b0\u1ee3ng do nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y t\u1ecfa ra \u0111\u01b0\u1ee3c bi\u1ebfn th\u00e0nh c\u00f4ng c\u00f3 \u00edch."],"hint":"","explain":"<span class='basic_left'>Hi\u1ec7u su\u1ea5t cho bi\u1ebft c\u00f3 bao nhi\u00eau ph\u1ea7n tr\u0103m nhi\u1ec7t l\u01b0\u1ee3ng do nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y t\u1ecfa ra \u0111\u01b0\u1ee3c bi\u1ebfn th\u00e0nh c\u00f4ng c\u00f3 \u00edch.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span><\/span> ","column":1}]}],"id_ques":3001},{"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 \u00f4t\u00f4 ch\u1ea1y 100km v\u1edbi l\u1ef1c k\u00e9o kh\u00f4ng \u0111\u1ed5i l\u00e0 700N th\u00ec ti\u00eau th\u1ee5 h\u1ebft 6 l\u00edt x\u0103ng. T\u00ednh hi\u1ec7u su\u1ea5t c\u1ee7a \u0111\u1ed9ng c\u01a1 \u0111\u00f3 bi\u1ebft n\u0103ng su\u1ea5t t\u1ecfa nhi\u1ec7t c\u1ee7a x\u0103ng l\u00e0 4,6.${10}^{7}$J\/kg, kh\u1ed1i l\u01b0\u1ee3ng ri\u00eang c\u1ee7a x\u0103ng l\u00e0 $700kg\/{{m}^{3}}$.","select":["A. H= 0,36.","B. H= 0,63.","C. H= 0,72.","D. H= 0,18."],"hint":"","explain":"<span class='basic_left'>Ta c\u00f3: $A=F\\times s=700\\times 100000=70000000J$ <br\/>$Q=q\\times m=4,6\\times {{10}^{7}}\\times 4,2=193200000J$ <br\/>Hi\u1ec7u su\u1ea5t c\u1ee7a \u0111\u1ed9ng c\u01a1 l\u00e0:<br\/>$H=\\dfrac{A}{Q}=\\dfrac{70000000}{193200000}=0,36$% <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span> ","column":2}]}],"id_ques":3002},{"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":"M\u1ed9t \u00f4 t\u00f4 ch\u1ea1y \u0111\u01b0\u1ee3c qu\u00e3ng \u0111\u01b0\u1eddng 100 km v\u1edbi l\u1ef1c k\u00e9o trung b\u00ecnh l\u00e0 700 N, ti\u00eau th\u1ee5 h\u1ebft 5 l\u00edt x\u0103ng (kho\u1ea3ng 4kg). T\u00ednh hi\u1ec7u su\u1ea5t c\u1ee7a \u0111\u1ed9ng c\u01a1 \u00f4 t\u00f4.","select":["A. 35,04%.","B. 36,04%.","C. 37,04%.","D. 38,04%."],"hint":"","explain":"<span class='basic_left'>C\u00f4ng \u0111\u1ed9ng c\u01a1 \u00f4 t\u00f4 th\u1ef1c hi\u1ec7n l\u00e0:<br\/>$A=F\\times S=700\\times 100000=7\\times {{10}^{7}}J$ <br\/>Nhi\u1ec7t l\u01b0\u1ee3ng do nhi\u00ean li\u1ec7u ch\u00e1y t\u1ecfa ra l\u00e0:<br\/>$Q=m\\times q=4 \\times 4,6\\times {{10}^{7}}=18,4\\times {{10}^{7}}J$ <br\/>Hi\u1ec7u su\u1ea5t c\u1ee7a \u0111\u1ed9ng c\u01a1 \u00f4 t\u00f4 l\u00e0:<br\/>$H=\\dfrac{A}{Q}\\times 100=\\dfrac{7\\times {{10}^{7}}}{18,4\\times {{10}^{7}}}\\times 100=38,04$% <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span><\/span> ","column":2}]}],"id_ques":3003},{"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":"Trong th\u1ef1c t\u1ebf hi\u1ec7u su\u1ea5t c\u1ee7a \u0111\u1ed9ng c\u01a1 nhi\u1ec7t th\u01b0\u1eddng c\u00f3 gi\u00e1 tr\u1ecb kho\u1ea3ng:","select":["A. 100%.","B. T\u1eeb 30% \u0111\u1ebfn 40%.","C. T\u1eeb 80% \u0111\u1ebfn 90%.","D. Tr\u00ean 90%."],"hint":"","explain":"<span class='basic_left'>Trong th\u1ef1c t\u1ebf hi\u1ec7u su\u1ea5t c\u1ee7a \u0111\u1ed9ng c\u01a1 nhi\u1ec7t th\u01b0\u1eddng c\u00f3 gi\u00e1 tr\u1ecb kho\u1ea3ng 30% \u0111\u1ebfn 40%. <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> ","column":2}]}],"id_ques":3004},{"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":"\u0110\u1ed9ng c\u01a1 nhi\u1ec7t c\u00f3 th\u1ec3 g\u00e2y ra nh\u1eefng t\u00e1c h\u1ea1i n\u00e0o \u0111\u1ed1i v\u1edbi m\u00f4i tr\u01b0\u1eddng s\u1ed1ng c\u1ee7a ch\u00fang ta? ","select":["A. C\u1ea3 \u00f4 nhi\u1ec5m v\u1ec1 ti\u1ebfng \u1ed3n, \u00f4 nhi\u1ec5m m\u00f4i tr\u01b0\u1eddng v\u00e0 l\u00e0m t\u0103ng nhi\u1ec7t \u0111\u1ed9 c\u1ee7a kh\u00ed quy\u1ec3n.","B. Nhi\u1ec7t l\u01b0\u1ee3ng do \u0111\u1ed9ng c\u01a1 th\u1ea3i ra g\u00f3p ph\u1ea7n l\u00e0m t\u0103ng nhi\u1ec7t \u0111\u1ed9 c\u1ee7a kh\u00ed quy\u1ec3n.","C. \u00d4 nhi\u1ec5m v\u1ec1 ti\u1ebfng \u1ed3n.","D. \u00d4 nhi\u1ec5m m\u00f4i tr\u01b0\u1eddng v\u1ec1 kh\u00ed th\u1ea3i c\u1ee7a c\u00e1c \u0111\u1ed9ng c\u01a1 c\u00f3 nhi\u1ec1u ch\u1ea5t \u0111\u1ed9c."],"hint":"","explain":"<span class='basic_left'>\u0110\u1ed9ng c\u01a1 nhi\u1ec7t c\u00f3 th\u1ec3 g\u00e2y ra nh\u1eefng t\u00e1c h\u1ea1i n\u00e0o \u0111\u1ed1i v\u1edbi m\u00f4i tr\u01b0\u1eddng s\u1ed1ng c\u1ee7a ch\u00fang ta nh\u01b0 \u00f4 nhi\u1ec5m v\u1ec1 ti\u1ebfng \u1ed3n, \u00f4 nhi\u1ec5m m\u00f4i tr\u01b0\u1eddng v\u00e0 l\u00e0m t\u0103ng nhi\u1ec7t \u0111\u1ed9 c\u1ee7a kh\u00ed quy\u1ec3n.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span> ","column":1}]}],"id_ques":3005},{"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 xe ch\u1ea1y v\u1edbi v\u1eadn t\u1ed1c v = 72km\/h tr\u00ean su\u1ed1t \u0111o\u1ea1n \u0111\u01b0\u1eddng v\u1edbi l\u1ef1c ph\u00e1t \u0111\u1ed9ng c\u1ee7a \u0111\u1ed9ng c\u01a1 l\u00e0 F = 1000N. Hi\u1ec7u su\u1ea5t c\u1ee7a \u0111\u1ed9ng c\u01a1 xe l\u00e0 H = 20%. T\u00ednh l\u01b0\u1ee3ng nhi\u00ean li\u1ec7u c\u1ea7n thi\u1ebft cho 10km. Bi\u1ebft r\u1eb1ng n\u0103ng su\u1ea5t t\u1ecfa nhi\u1ec7t c\u1ee7a nhi\u00ean li\u1ec7u l\u00e0 $46\\times {{10}^{6}}$\/kg.","select":["A. m = 12,25kg.","B. m = 1,087kg.","C. m = 11,78kg.","D. m = 13,22kg."],"hint":"","explain":"<span class='basic_left'>C\u00f4ng \u0111\u1ed9ng c\u01a1 sinh ra khi \u0111i 10km l\u00e0: $A=F\\times S=1000\\times 10000={{10}^{7}}J$ <br\/>N\u0103ng l\u01b0\u1ee3ng do nhi\u00ean li\u1ec7u sinh ra l\u00e0: $Q=\\dfrac{A}{0,2}=5\\times {{10}^{7}}J$ <br\/>Kh\u1ed1i l\u01b0\u1ee3ng nhi\u00ean li\u1ec7u: $m=\\dfrac{Q}{q}=\\dfrac{5\\times {{10}^{7}}}{46\\times {{10}^{6}}}=1,087kg$ <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> ","column":2}]}],"id_ques":3006},{"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":"Trong c\u00e1c \u0111\u1ed9ng c\u01a1 sau \u0111\u00e2y, \u0111\u1ed9ng c\u01a1 n\u00e0o l\u00e0 \u0111\u1ed9ng c\u01a1 nhi\u1ec7t?","select":["A. \u0110\u1ed9ng c\u01a1 c\u1ee7a m\u00e1y xay sinh t\u1ed1.","B. \u0110\u1ed9ng c\u01a1 c\u1ee7a chi\u1ebfc xe m\u00e1y.","C. \u0110\u1ed9ng c\u01a1 c\u1ee7a m\u00e1y qu\u1ea1t.","D. \u0110\u1ed9ng c\u01a1 c\u1ee7a m\u00e1y gi\u1eb7t."],"hint":"","explain":"<span class='basic_left'>\u0110\u1ed9ng c\u01a1 c\u1ee7a chi\u1ebfc xe m\u00e1y l\u00e0 \u0111\u1ed9ng c\u01a1 nhi\u1ec7t. <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> ","column":2}]}],"id_ques":3007},{"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":"C\u00e1c k\u00ec c\u1ee7a \u0111\u1ed9ng c\u01a1 b\u1ed1n th\u00ec di\u1ec5n ra theo th\u1ee9 t\u1ef1:","select":["A. H\u00fat nhi\u00ean li\u1ec7u, \u0111\u1ed1t nhi\u00ean li\u1ec7u, n\u00e9n nhi\u00ean li\u1ec7u, tho\u00e1t kh\u00ed.","B. Tho\u00e1t kh\u00ed, h\u00fat nhi\u00ean li\u1ec7u, n\u00e9n nhi\u00ean li\u1ec7u, \u0111\u1ed1t nhi\u00ean li\u1ec7u.","C. H\u00fat nhi\u00ean li\u1ec7u, n\u00e9n nhi\u00ean li\u1ec7u, tho\u00e1t kh\u00ed, \u0111\u1ed1t nhi\u00ean li\u1ec7u.","D. H\u00fat nhi\u00ean li\u1ec7u, n\u00e9n nhi\u00ean li\u1ec7u, \u0111\u1ed1t nhi\u00ean li\u1ec7u, tho\u00e1t kh\u00ed."],"hint":"","explain":"<span class='basic_left'>C\u00e1c k\u00ec c\u1ee7a \u0111\u1ed9ng c\u01a1 b\u1ed1n th\u00ec di\u1ec5n ra theo th\u1ee9 t\u1ef1: H\u00fat nhi\u00ean li\u1ec7u, n\u00e9n nhi\u00ean li\u1ec7u, \u0111\u1ed1t nhi\u00ean li\u1ec7u, tho\u00e1t kh\u00ed<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span><\/span> ","column":1}]}],"id_ques":3008},{"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":"M\u1ed9t \u0111\u1ed9ng c\u01a1 n\u1ed5 4 th\u00ec, th\u1ec3 t\u00edch c\u1ee7a xi lanh l\u00e0 1,95 l\u00edt. Th\u1ec3 t\u00edch h\u1ed7n h\u1ee3p nhi\u00ean li\u1ec7u b\u1eb1ng 1,5 l\u1ea7n th\u1ec3 t\u00edch th\u1ec3 t\u00edch kh\u00f4ng kh\u00ed c\u1ea7n d\u00f9ng cho s\u1ef1 \u0111\u1ed1t ch\u00e1y ho\u00e0n to\u00e0n. Khi v\u00f4 l\u0103ng quay 200 v\u00f2ng, th\u1ec3 t\u00edch kh\u00f4ng kh\u00ed c\u1ea7n d\u00f9ng l\u00e0 bao nhi\u00eau?","select":["A. V = 150 l\u00edt.","B. V = 140 l\u00edt.","C. V = 120 l\u00edt.","D. V = 130 l\u00edt."],"hint":"","explain":"<span class='basic_left'>Th\u1ec3 t\u00edch kh\u00f4ng kh\u00ed c\u1ea7n trong m\u1ed9t chu k\u1ef3 l\u00e0:<br\/>${{V}_{1}}=\\dfrac{1,95}{1,5}=1,3l$<br\/>Khi v\u00f4 l\u0103ng quay 200 v\u00f2ng th\u00ec t\u01b0\u01a1ng \u1ee9ng l\u00e0 100 chu k\u1ef3, v\u1eady t\u1ed5ng th\u1ec3 t\u00edch kh\u00ed l\u00e0:<br\/>$V=100{{V}_{1}}=130l$ <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span><\/span> ","column":2}]}],"id_ques":3009},{"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":"\u0110\u1ed9ng c\u01a1 nhi\u1ec7t l\u00e0:","select":["A. \u0110\u1ed9ng c\u01a1 trong \u0111\u00f3 to\u00e0n b\u1ed9 ph\u1ea7n n\u0103ng l\u01b0\u1ee3ng c\u1ee7a nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y chuy\u1ec3n h\u00f3a th\u00e0nh c\u01a1 n\u0103ng.","B. \u0110\u1ed9ng c\u01a1 trong \u0111\u00f3 m\u1ed9t ph\u1ea7n n\u0103ng l\u01b0\u1ee3ng c\u1ee7a nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y chuy\u1ec3n h\u00f3a th\u00e0nh nhi\u1ec7t n\u0103ng.","C. \u0110\u1ed9ng c\u01a1 trong \u0111\u00f3 m\u1ed9t ph\u1ea7n n\u0103ng l\u01b0\u1ee3ng c\u1ee7a nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y chuy\u1ec3n h\u00f3a th\u00e0nh c\u01a1 n\u0103ng.","D. \u0110\u1ed9ng c\u01a1 trong \u0111\u00f3 to\u00e0n b\u1ed9 ph\u1ea7n n\u0103ng l\u01b0\u1ee3ng c\u1ee7a nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y chuy\u1ec3n h\u00f3a th\u00e0nh nhi\u1ec7t n\u0103ng."],"hint":"","explain":"<span class='basic_left'>\u0110\u1ed9ng c\u01a1 nhi\u1ec7t l\u00e0 \u0111\u1ed9ng c\u01a1 trong \u0111\u00f3 m\u1ed9t ph\u1ea7n n\u0103ng l\u01b0\u1ee3ng c\u1ee7a nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y chuy\u1ec3n h\u00f3a th\u00e0nh c\u01a1 n\u0103ng.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> ","column":1}]}],"id_ques":3010},{"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":"Bi\u1ebfu th\u1ee9c n\u00e0o sau \u0111\u00e2y x\u00e1c \u0111\u1ecbnh hi\u1ec7u su\u1ea5t c\u1ee7a \u0111\u1ed9ng c\u01a1 nhi\u1ec7t?","select":["A. $H=\\dfrac{Q}{A}$.","B. $H=A-Q$.","C. $H=\\dfrac{A}{Q}$.","D. $H=Q-A$."],"hint":"","explain":"<span class='basic_left'>$H=\\dfrac{A}{Q}$.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> ","column":2}]}],"id_ques":3011},{"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\u1edbi 4 l\u00edt x\u0103ng, m\u1ed9t xe m\u00e1y c\u00f3 c\u00f4ng su\u1ea5t 1,6 kW chuy\u1ec3n \u0111\u1ed9ng v\u1edbi v\u1eadn t\u1ed1c 36km\/h s\u1ebd \u0111i \u0111\u01b0\u1ee3c bao nhi\u00eau km? Bi\u1ebft hi\u1ec7u su\u1ea5t c\u1ee7a \u0111\u1ed9ng c\u01a1 l\u00e0 30%, n\u0103ng su\u1ea5t t\u1ecfa nhi\u1ec7t c\u1ee7a x\u0103ng l\u00e0 $4,6\\times {{10}^{7}}$J\/kg, kh\u1ed1i l\u01b0\u1ee3ng ri\u00eang c\u1ee7a x\u0103ng l\u00e0 700kg\/${{m}^{3}}$ . Ch\u1ecdn k\u1ebft qu\u1ea3 \u0111\u00fang trong c\u00e1c k\u1ebft qu\u1ea3 sau:","select":["A. M\u1ed9t k\u1ebft qu\u1ea3 kh\u00e1c.","B. S = 24,15km.","C. S = 241,5km.","D. S = 2415km."],"hint":"","explain":"<span class='basic_left'>\u0110\u1ed5i 36km\/h= 10m\/s<br\/> L\u1ef1c ph\u00e1t \u0111\u1ed9ng c\u1ee7a \u0111\u1ed9ng c\u01a1: $F=\\dfrac{P}{v}=\\dfrac{1600}{10}=160N$ <br\/> L\u01b0\u1ee3ng nhi\u1ec7t do x\u0103ng sinh ra l\u00e0: $Q=4\\times 0,7\\times 4,6\\times {{10}^{7}}=12,88\\times {{10}^{7}}J$ <br\/> C\u00f4ng do \u0111\u1ed9ng c\u01a1 th\u1ef1c hi\u1ec7n $A=Q\\times 0,3=3,864\\times {{10}^{7}}J$ <br\/> Qu\u00e3ng \u0111\u01b0\u1eddng xe \u0111i \u0111\u01b0\u1ee3c: $S=\\dfrac{A}{F}=\\dfrac{3,864\\times {{10}^{7}}}{160}=241500m=241,5km$ <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> ","column":2}]}],"id_ques":3012},{"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\u1ed9ng c\u01a1 c\u1ee7a m\u1ed9t m\u00e1y bay c\u00f3 c\u00f4ng su\u1ea5t $2\\times {{10}^{6}}$W v\u00e0 hi\u1ec7u su\u1ea5t 30%. H\u1ecfi v\u1edbi m\u1ed9t t\u1ea5n x\u0103ng, m\u00e1y bay c\u00f3 th\u1ec3 bay \u0111\u01b0\u1ee3c bao l\u00e2u? N\u0103ng su\u1ea5t t\u1ecfa nhi\u1ec7t c\u1ee7a x\u0103ng l\u00e0 $4,6\\times {{10}^{7}}$ J\/kg.","select":["A. t = 1 gi\u1edd.","B. t = 1 gi\u1edd 45 ph\u00fat.","C. t = 1 gi\u1edd 25 ph\u00fat.","D. t = 1 gi\u1edd 55 ph\u00fat."],"hint":"","explain":"<span class='basic_left'>Nhi\u1ec7t l\u01b0\u1ee3ng do x\u0103ng sinh ra:<br\/> $Q=m\\times q=1000\\times 4,6\\times {{10}^{7}}=4,6\\times {{10}^{10}}J$ <br\/> C\u00f4ng c\u1ee7a \u0111\u1ed9ng c\u01a1:$A=0,3\\times Q$ <br\/> Th\u1eddi gian bay:<br\/> $t=\\dfrac{A}{P}=\\dfrac{0,3\\times 4,6\\times {{10}^{10}}}{2\\times {{10}^{6}}}=6900s=1h55m$ <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span><\/span> ","column":2}]}],"id_ques":3013},{"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 \u00f4 t\u00f4 ch\u1ea1y \u0111\u01b0\u1ee3c qu\u00e3ng \u0111\u01b0\u1eddng 100km v\u1edbi l\u1ef1c k\u00e9o trung b\u00ecnh l\u00e0 700N, ti\u00eau th\u1ee5 h\u1ebft 5 l\u00edt x\u0103ng (kho\u1ea3ng 4 kg). Hi\u1ec7u su\u1ea5t c\u1ee7a \u0111\u1ed9ng c\u01a1 c\u00f3 th\u1ec3 l\u00e0?","select":["A. H = 380,4%.","B. H = 38,04%.","C. H = 3804%.","D. M\u1ed9t gi\u00e1 tr\u1ecb kh\u00e1c."],"hint":"","explain":"<span class='basic_left'>Nhi\u1ec7t l\u01b0\u1ee3ng do x\u0103ng sinh ra:<br\/> $Q=m\\times q=4\\times 4,6\\times {{10}^{7}}=18,4\\times {{10}^{7}}J$ <br\/> C\u00f4ng c\u1ee7a \u0111\u1ed9ng c\u01a1:<br\/> $A=F\\times S=100000\\times 700=7\\times {{10}^{7}}J$ <br\/> Hi\u1ec7u su\u1ea5t: $H=\\dfrac{A}{Q}=\\dfrac{7}{18,4}=38,4$% <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> ","column":2}]}],"id_ques":3014},{"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":"C\u00e2u n\u00e0o sau \u0111\u00e2y n\u00f3i v\u1ec1 hi\u1ec7u su\u1ea5t c\u1ee7a \u0111\u1ed9ng c\u01a1 nhi\u1ec7t?","select":["A. Hi\u1ec7u su\u1ea5t cho bi\u1ebft \u0111\u1ed9ng c\u01a1 m\u1ea1nh hay y\u1ebfu.","B. Hi\u1ec7u su\u1ea5t cho bi\u1ebft \u0111\u1ed9ng c\u01a1 th\u1ef1c hi\u1ec7n c\u00f4ng nhanh hay ch\u1eadm.","C. Hi\u1ec7u su\u1ea5t cho bi\u1ebft nhi\u1ec7t l\u01b0\u1ee3ng t\u1ecfa ra khi 1kg nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y ho\u00e0n to\u00e0n trong \u0111\u1ed9ng c\u01a1.","D. Hi\u1ec7u su\u1ea5t cho bi\u1ebft \u0111\u1ed9ng c\u01a1 c\u00f3 bao nhi\u00eau ph\u1ea7n tr\u0103m nhi\u1ec7t l\u01b0\u1ee3ng do nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y t\u1ecfa ra \u0111\u01b0\u1ee3c bi\u1ebfn th\u00e0nh c\u00f4ng c\u00f3 \u00edch."],"hint":"","explain":"<span class='basic_left'>Hi\u1ec7u su\u1ea5t cho bi\u1ebft \u0111\u1ed9ng c\u01a1 c\u00f3 bao nhi\u00eau ph\u1ea7n tr\u0103m nhi\u1ec7t l\u01b0\u1ee3ng do nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y t\u1ecfa ra \u0111\u01b0\u1ee3c bi\u1ebfn th\u00e0nh c\u00f4ng c\u00f3 \u00edch.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span><\/span> ","column":1}]}],"id_ques":3015},{"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\u1eeb c\u00f4ng th\u1ee9c $H=\\dfrac{A}{Q}$, ta c\u00f3 th\u1ec3 suy ra l\u00e0 \u0111\u1ed1i v\u1edbi m\u1ed9t xe \u00f4 t\u00f4 ch\u1ea1y b\u1eb1ng \u0111\u1ed9ng c\u01a1 nhi\u1ec7t th\u00ec:","select":["A. C\u00f4ng m\u00e0 \u0111\u1ed9ng c\u01a1 sinh ra t\u1ec9 l\u1ec7 v\u1edbi kh\u1ed1i l\u01b0\u1ee3ng nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y.","B. C\u00f4ng su\u1ea5t c\u1ee7a \u0111\u1ed9ng c\u01a1 t\u1ec9 l\u1ec7 v\u1edbi kh\u1ed1i l\u01b0\u1ee3ng nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y.","C. V\u1eadn t\u1ed1c c\u1ee7a xe t\u1ec9 l\u1ec7 v\u1edbi kh\u1ed1i l\u01b0\u1ee3ng nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y.","D. Qu\u00e3ng \u0111\u01b0\u1eddng xe \u0111i \u0111\u01b0\u1ee3c t\u1ec9 l\u1ec7 v\u1edbi kh\u1ed1i l\u01b0\u1ee3ng nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y."],"hint":"","explain":"<span class='basic_left'>T\u1eeb c\u00f4ng th\u1ee9c $H=\\dfrac{A}{Q}$, ta c\u00f3 th\u1ec3 suy ra l\u00e0 \u0111\u1ed1i v\u1edbi m\u1ed9t xe \u00f4 t\u00f4 ch\u1ea1y b\u1eb1ng \u0111\u1ed9ng c\u01a1 nhi\u1ec7t th\u00ec: c\u00f4ng m\u00e0 \u0111\u1ed9ng c\u01a1 sinh ra t\u1ec9 l\u1ec7 v\u1edbi kh\u1ed1i l\u01b0\u1ee3ng nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y. <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span> ","column":1}]}],"id_ques":3016},{"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 m\u00e1y b\u01a1m n\u01b0\u1edbc sau khi ti\u00eau th\u1ee5 h\u1ebft 8kg d\u1ea7u th\u00ec \u0111\u01b0a \u0111\u01b0\u1ee3c $900{{m}^{3}}$. n\u01b0\u1edbc l\u00ean cao 10m. Hi\u1ec7u su\u1ea5t c\u1ee7a m\u00e1y b\u01a1m \u0111\u00f3 l\u00e0 bao nhi\u00eau? Bi\u1ebft n\u0103ng su\u1ea5t t\u1ecfa nhi\u1ec7t c\u1ee7a d\u1ea7u d\u00f9ng cho m\u00e1y b\u01a1m l\u00e0 $4,6\\times {{10}^{7}}J\/kg$, kh\u1ed1i l\u01b0\u1ee3ng ri\u00eang c\u1ee7a n\u01b0\u1edbc l\u00e0 $1000kg\/{{m}^{3}}$.","select":["A. $24,46%$.","B. $2,45%$.","C. $15,22%$.","D. $1,52%$."],"hint":"","explain":"<span class='basic_left'>C\u00f4ng th\u1ef1c hi\u1ec7n l\u00e0: $A=mgh=900\\times {{10}^{3}}\\times 10\\times 10=9\\times {{10}^{7}}J$ <br\/>Nhi\u1ec7t t\u1ecfa ra c\u1ee7a x\u0103ng l\u00e0: $Q=m\\times q=8\\times 4,6\\times {{10}^{7}}=36,8\\times {{10}^{7}}J$<br\/>Hi\u1ec7u su\u1ea5t l\u00e0: $H=\\dfrac{A}{Q}=24,46$% <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span> ","column":2}]}],"id_ques":3017},{"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":"G\u1ecdi H l\u00e0 hi\u1ec7u su\u1ea5t c\u1ee7a \u0111\u1ed9ng c\u01a1 nhi\u1ec7t, A l\u00e0 c\u00f4ng \u0111\u1ed9ng c\u01a1 th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c, Q l\u00e0 nhi\u1ec7t l\u01b0\u1ee3ng to\u00e0n ph\u1ea7n do nhi\u00ean li\u1ec7u b\u1ecb \u0111\u1ed1t ch\u00e1y t\u1ecfa ra, ${{Q}_{1}}$ l\u00e0 nhi\u1ec7t l\u01b0\u1ee3ng c\u00f3 \u00edch, ${{Q}_{2}}$ l\u00e0 nhi\u1ec7t l\u01b0\u1ee3ng t\u1ecfa ra m\u00f4i tr\u01b0\u1eddng b\u00ean ngo\u00e0i. C\u00f4ng th\u1ee9c t\u00ednh hi\u1ec7u su\u1ea5t n\u00e0o sau \u0111\u00e2y l\u00e0 \u0111\u00fang?","select":["A. $H=\\dfrac{{{Q}_{1}}-{{Q}_{2}}}{Q}$.","B. $H=\\dfrac{{{Q}_{2}}-{{Q}_{1}}}{Q}$.","C. $H=\\dfrac{Q-{{Q}_{2}}}{Q}$.","D. $H=\\dfrac{{{Q}_{2}}}{Q}$."],"hint":"","explain":"<span class='basic_left'>$H=\\dfrac{Q-{{Q}_{2}}}{Q}$.<br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> ","column":2}]}],"id_ques":3018},{"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\u1edbi 2 l\u00edt x\u0103ng, m\u1ed9t xe m\u00e1y c\u00f3 c\u00f4ng su\u1ea5t 3,2 kW chuy\u1ec3n \u0111\u1ed9ng v\u1edbi v\u1eadn t\u1ed1c 45 km\/h s\u1ebd \u0111i \u0111\u01b0\u1ee3c bao nhi\u00eau km? Bi\u1ebft hi\u1ec7u su\u1ea5t c\u1ee7a \u0111\u1ed9ng c\u01a1 l\u00e0 25%, n\u0103ng su\u1ea5t t\u1ecfa nhi\u1ec7t c\u1ee7a x\u0103ng l\u00e0 $4,6\\times {{10}^{7}}J\/kg$, kh\u1ed1i l\u01b0\u1ee3ng ri\u00eang c\u1ee7a x\u0103ng l\u00e0 $700kg\/{{m}^{3}}$.","select":["A. 100,62 km.","B. 62,9 km.","C. 45 km.","D. 54 km."],"hint":"","explain":"<span class='basic_left'>\u0110\u1ed5i 45km\/h= 12,5m\/s<br\/>L\u1ef1c ph\u00e1t \u0111\u1ed9ng c\u1ee7a \u0111\u1ed9ng c\u01a1: $F=\\dfrac{P}{v}=\\dfrac{3200}{12,5}=256N$ <br\/>L\u01b0\u1ee3ng nhi\u1ec7t do x\u0103ng sinh ra l\u00e0: $Q=2\\times 0,7\\times 4,6\\times {{10}^{7}}=6,44\\times {{10}^{7}}J$ <br\/>C\u00f4ng do \u0111\u1ed9ng c\u01a1 th\u1ef1c hi\u1ec7n $A=Q\\times 0,25=1,61\\times {{10}^{7}}J$ <br\/>Qu\u00e3ng \u0111\u01b0\u1eddng xe \u0111i \u0111\u01b0\u1ee3c: $S=\\dfrac{A}{F}=\\dfrac{1,61\\times {{10}^{7}}}{256}=62890m=62,9km$ <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> ","column":2}]}],"id_ques":3019}],"lesson":{"save":0,"level":2}}