C\u00e2u 1:<\/b>\u00a0Ho\u1ea1t \u0111\u1ed9ng c\u1ee7a m\u1ea1ch ch\u1ecdn s\u00f3ng c\u1ee7a m\u00e1y thu thanh d\u1ef1a v\u00e0o hi\u1ec7n t\u01b0\u1ee3ng<\/p>\n

A. truy\u1ec1n s\u00f3ng \u0111i\u1ec7n t\u1eeb\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 B. h\u1ea5p th\u1ee5 s\u00f3ng \u0111i\u1ec7n t\u1eeb<\/p>\n

C. Giao thoa s\u00f3ng \u0111i\u1ec7n t\u1eeb\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D. c\u1ed9ng d\u01b0\u1edfng \u0111i\u1ec7n t\u1eeb<\/p>\n

C\u00e2u 2:<\/b>\u00a0K\u00ed hi\u1ec7u c\u00e1c m\u1ea1ch trong m\u00e1y thu thanh v\u00e0 ph\u00e1t thanh nh\u01b0 sau: (1) m\u1ea1ch t\u00e1ch s\u00f3ng ; (2) m\u1ea1ch khu\u1ebfch \u0111\u1ea1i \u00e2m t\u1ea7n ; (3) m\u1ea1ch khu\u1ebfch \u0111\u1ea1i cao t\u1ea7n ; (4) m\u1ea1ch bi\u1ebfn \u0111i\u1ec7u.<\/p>\n

Trong s\u01a1 \u0111\u1ed3 c\u1ee7a m\u1ed9t m\u00e1y thu thanh v\u00f4 tuy\u1ebfn \u0111i\u1ec7n, kh\u00f4ng c\u00f3 m\u1ea1ch n\u00e0o k\u1ec3 tr\u00ean?<\/p>\n

A. (1) v\u00e0 (2)\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 B. (3)<\/p>\n

C. (3) v\u00e0 (4)\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D. (4)<\/p>\n

C\u00e2u 3:<\/b>\u00a0K\u00ed hi\u1ec7u c\u00e1c m\u1ea1ch trong m\u00e1y thu v\u00f4 tuy\u1ebfn \u0111i\u1ec7n nh\u01b0 sau: : (1) m\u1ea1ch t\u00e1ch s\u00f3ng ; (2) m\u1ea1ch khu\u1ebfch \u0111\u1ea1i ; (3) m\u1ea1ch bi\u1ebfn \u0111i\u1ec7u ; (4) m\u1ea1ch ch\u1ecdn s\u00f3ng.<\/p>\n

Trong c\u00e1c m\u00e1y thu thanh, m\u00e1y thu h\u00ecnh, m\u1ea1ch n\u00e0o n\u00eau tr\u00ean ho\u1ea1t \u0111\u1ed9ng d\u1ef1a tr\u00ean hi\u1ec7n t\u01b0\u1ee3ng c\u1ed9ng h\u01b0\u1edfng \u0111i\u1ec7n t\u1eeb?<\/p>\n

A. (1)\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 B. (4)<\/p>\n

C. (2) v\u00e0 (3)\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D. (1) v\u00e0 (4)<\/p>\n

C\u00e2u 4:<\/b>\u00a0M\u1ea1ch ch\u1ecdn s\u00f3ng c\u1ee7a m\u00e1y thu v\u00f4 tuy\u1ebfn \u0111i\u1ec7n g\u1ed3m cu\u1ed9n c\u1ea3m thu\u1ea7n c\u00f3 \u0111\u1ed9 t\u1ef1 c\u1ea3m 0,1 mH v\u00e0 t\u1ee5 \u0111i\u1ec7n c\u00f3 \u0111i\u1ec7n dung bi\u1ebfn thi\u00ean t\u1eeb 2,5 nF \u0111\u1ebfn 10 nF. Cho t\u1ed1c \u0111\u1ed9 \u00e1nh s\u00e1ng trong ch\u00e2n kh\u00f4ng l\u00e0 c=3.10^{8<\/sup>\u00a0m\/s. M\u00e1y thu n\u00e0y c\u00f3 th\u1ec3 thu \u0111\u01b0\u1ee3c s\u00f3ng \u0111i\u1ec7n t\u1eeb c\u00f3 b\u01b0\u1edbc s\u00f3ng n\u1eb1m trong kho\u1ea3ng<\/p>\n}

A. t\u1eeb 18,84 m \u0111\u1ebfn 56,52 m\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 B. t\u1eeb 56,52 m \u0111\u1ebfn 94,2 m<\/p>\n

C. t\u1eeb 942 m \u0111\u1ebfn 1884 m\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D. t\u1eeb 188,4 m \u0111\u1ebfn 565,2 m<\/p>\n

C\u00e2u 5:<\/b>\u00a0Khi m\u1eafc t\u1ee5 \u0111i\u1ec7n c\u00f3 \u0111i\u1ec7n dung C_{1<\/sub>\u00a0v\u1edbi cu\u1ed9n c\u1ea3m L th\u1ecb t\u1ea1o m\u1ea1ch dao \u0111\u1ed9ng \u0111i\u1ec7n t\u1eeb c\u00f3 th\u1ec3 thu \u0111\u01b0\u1ee3c s\u00f3ng \u0111i\u1ec7n t\u1eeb c\u00f3 b\u01b0\u1edbc s\u00f3ng 30 m ; khi m\u1eafc t\u1ee5 \u0111i\u1ec7n c\u00f3 \u0111i\u1ec7n dung C2<\/sub>\u00a0v\u1edbi cu\u1ed9n c\u1ea3m L th\u00ec t\u1ea1o ra m\u1ea1ch dao \u0111\u1ed9ng \u0111i\u1ec7n t\u1eeb c\u00f3 th\u1ec3 thu \u0111\u01b0\u1ee3c s\u00f3ng \u0111i\u1ec7n t\u1eeb c\u00f3 b\u01b0\u1edbc s\u00f3ng 40 m. Khi m\u1eafc (C1<\/sub>\u00a0song song C2<\/sub>) r\u1ed3i m\u1eafc v\u1edbi cu\u1ed9n L th\u00ec t\u1ea1o ra m\u1ea1ch dao \u0111\u1ed9ng thu \u0111\u01b0\u1ee3c s\u00f3ng \u0111i\u1ec7n t\u1eeb c\u00f3 b\u01b0\u1edbc s\u00f3ng l\u00e0<\/p>\n}

A. 50 m\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 B. 10 m\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 C. 70 m\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D. 35 m<\/p>\n

C\u00e2u 6:<\/b>\u00a0M\u1ed9t m\u1ea1ch ch\u1ecdn s\u00f3ng c\u1ee7a m\u1ed9t m\u00e1y thu v\u00f4 tuy\u1ebfn \u0111i\u1ec7n g\u1ed3m m\u1ed9t cu\u1ed9n d\u00e2y c\u00f3 \u0111\u1ed9 t\u1ef1 c\u1ea3m L v\u00e0 m\u1ed9t b\u1ed9 t\u1ee5 \u0111i\u1ec7n g\u1ed3m m\u1ed9t t\u1ee5 \u0111i\u1ec7n c\u1ed1 \u0111\u1ecbnh C_{o<\/sub>\u00a0m\u1eafc song song v\u1edbi m\u1ed9t t\u1ee5 \u0111i\u1ec7n C. T\u1ee5 \u0111i\u1ec7n C c\u00f3 \u0111i\u1ec7n dung thay \u0111\u1ed5i t\u1eeb 10 nF \u0111\u1ebfn 170 nF. Nh\u1edd v\u1eady m\u00e0 m\u1ea1ch c\u00f3 th\u1ec3 thu \u0111\u01b0\u1ee3c c\u00e1c s\u00f3ng v\u00f4 tuy\u1ebfn c\u00f3 b\u01b0\u1edbc s\u00f3ng t\u1eeb \u03bb \u0111\u1ebfn 3\u03bb. \u0110i\u1ec7n dung c\u1ee7a t\u1ee5 \u0111i\u1ec7n Co<\/sub>\u00a0l\u00e0<\/p>\n}

A. 30 nF\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 B. 10 nF\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 C. 25 nF\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D. 45 nF<\/p>\n

C\u00e2u 7:<\/b>\u00a0M\u1ed9t m\u1ea1ch dao \u0111\u1ed9ng \u0111i\u1ec7n t\u1eeb d\u00f9ng \u0111\u1ec3 ch\u1ecdn s\u00f3ng c\u1ee7a m\u00e1y thu v\u00f4 tuy\u1ebfn \u0111i\u1ec7n g\u1ed3m m\u1ed9t t\u1ee5 \u0111i\u1ec7n c\u00f3 \u0111i\u1ec7n dung C v\u00e0 cu\u1ed9n c\u1ea3m thu\u1ea7n c\u00f3 \u0111\u1ed9 t\u1ef1 c\u1ea3m L thay \u0111\u1ed5i \u0111\u01b0\u1ee3c. Khi \u0111i\u1ec1u ch\u1ec9nh L=L_{o<\/sub>\u00a0m\u00e1y thu \u0111\u01b0\u1ee3c s\u00f3ng \u0111i\u1ec7n t\u1eeb c\u00f3 b\u01b0\u1edbc s\u00f3ng \u03bb, \u0111\u1ec3 m\u00e1y thu \u0111\u01b0\u1ee3c s\u00f3ng \u0111i\u1ec7n t\u1eeb c\u00f3 b\u01b0\u1edbc s\u00f3ng 2\u03bb th\u00ec ph\u1ea3i \u0111i\u1ec1u ch\u1ec9nh \u0111\u1ed9 t\u1ef1 c\u1ea3m L \u0111\u1ebfn gi\u00e1 tr\u1ecb<\/p>\n}

A. 3L_{o<\/sub>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 B. Lo<\/sub><\/p>\n}

C. 2L_{o<\/sub>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D. 4Lo<\/sub><\/p>\n}

C\u00e2u 8:<\/b>\u00a0M\u1ed9t m\u1ea1ch dao \u0111\u1ed9ng \u0111i\u1ec7n t\u1eeb g\u1ed3m m\u1ed9t cu\u1ed9n c\u1ea3m L khi m\u1eafc n\u1ed1i ti\u1ebfp v\u1edbi t\u1ee5 \u0111i\u1ec7n C_{1<\/sub>\u00a0th\u00ec thu \u0111\u01b0\u1ee3c s\u00f3ng \u0111i\u1ec7n t\u1eeb c\u00f3 b\u01b0\u1edbc s\u00f3ng \u03bb1<\/sub>, c\u00f2n khi thay b\u1eb1ng t\u1ee5 tr\u00ean b\u1eb1ng t\u1ee5 C2<\/sub>\u00a0th\u00ec m\u1ea1ch thu \u0111\u01b0\u1ee3c s\u00f3ng \u0111i\u1ec7n t\u1eeb c\u00f3 b\u01b0\u1edbc s\u00f3ng \u03bb2<\/sub>. N\u1ebfu m\u1eafc \u0111\u1ed3ng th\u1eddi hai t\u1ee5 n\u1ed1i ti\u1ebfp v\u1edbi nhau r\u1ed3i n\u1ed1i v\u1edbi cu\u1ed9n d\u00e2y th\u00ec m\u1ea1ch thu \u0111\u01b0\u1ee3c s\u00f3ng \u0111i\u1ec7n t\u1eeb c\u00f3 b\u01b0\u1edbc s\u00f3ng b\u1eb1ng<\/p>\n}

<\/p>\n

H\u01b0\u1edbng d\u1eabn gi\u1ea3i v\u00e0 \u0111\u00e1p \u00e1n<\/b><\/p>\n\n\n\n\n

C\u00e2u<\/td>\n	1<\/td>\n	2<\/td>\n	3<\/td>\n	4<\/td>\n	5<\/td>\n	6<\/td>\n	7<\/td>\n	8<\/td>\n<\/tr>\n
\u0110\u00e1p \u00e1n<\/td>\n	D<\/td>\n	D<\/td>\n	B<\/td>\n	C<\/td>\n	A<\/td>\n	B<\/td>\n	D<\/td>\n	C<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n C\u00e2u 4:<\/b>\u00a0C<\/p>\n <\/p>\n C\u00e2u 5:<\/b>\u00a0A<\/p>\n <\/p>\n C\u00e2u 6:<\/b>\u00a0B<\/p>\n <\/p>\n C\u00e2u 8:<\/b>\u00a0C<\/p>\n <\/p>\n","protected":false},"excerpt":{"rendered":" C\u00e2u 1:\u00a0Ho\u1ea1t \u0111\u1ed9ng c\u1ee7a m\u1ea1ch ch\u1ecdn s\u00f3ng c\u1ee7a m\u00e1y thu thanh d\u1ef1a v\u00e0o hi\u1ec7n t\u01b0\u1ee3ng A. truy\u1ec1n s\u00f3ng \u0111i\u1ec7n t\u1eeb\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 B. h\u1ea5p th\u1ee5 s\u00f3ng \u0111i\u1ec7n t\u1eeb C. Giao thoa s\u00f3ng \u0111i\u1ec7n t\u1eeb\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D. c\u1ed9ng d\u01b0\u1edfng \u0111i\u1ec7n t\u1eeb C\u00e2u 2:\u00a0K\u00ed hi\u1ec7u c\u00e1c m\u1ea1ch trong m\u00e1y thu thanh v\u00e0 ph\u00e1t thanh nh\u01b0 sau: (1) m\u1ea1ch t\u00e1ch s\u00f3ng […]<\/p>\n","protected":false},"author":3,"featured_media":25876,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_mi_skip_tracking":false,"tdm_status":"","tdm_grid_status":""},"categories":[158],"tags":[1443,1442],"yoast_head":"\n