C\u00e2u 1:<\/b>\u00a0T\u1ea1i c\u00f9ng m\u1ed9t v\u1ecb tr\u00ed \u0111\u1ecba l\u00ed, n\u1ebfu \u0111\u1ed9 d\u00e0i con l\u1eafc \u0111\u01a1n t\u0103ng 6,25 l\u1ea7n, th\u00ec s\u1ed1 dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u1ee7a n\u00f3<\/p>\n

A. t\u0103ng 2 l\u1ea7n. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0B. gi\u1ea3m 2,5 l\u1ea7n. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0C. gi\u1ea3m 1,5 l\u1ea7n. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0D. t\u0103ng 4 l\u1ea7n.<\/p>\n

C\u00e2u 2:<\/b>\u00a0C\u00f3 hai con l\u1eafc \u0111\u01a1n m\u00e0 \u0111\u1ed9 d\u00e0i c\u1ee7a ch\u00fang h\u01a1n k\u00e9m nhau 24 cm. Trong c\u00f9ng m\u1ed9t kho\u1ea3ng th\u1eddi gian, con l\u1eafc (l) th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c s\u1ed1 dao \u0111\u1ed9ng g\u1ea5p 2 l\u1ea7n so v\u1edbi con l\u1eafc (2). \u0110\u1ed9 d\u00e0i c\u1ee7a m\u1ed7i con l\u1eafc l\u00e0<\/p>\n

A. 32 cm v\u00e0 56 cm \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0B. 16 cm v\u00e0 40 cm<\/p>\n

C. 32 cm v\u00e0 8 cm \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0D. 16 cm v\u00e0 32 cm<\/p>\n

C\u00e2u 3:<\/b>\u00a0M\u1ed9t con l\u1eafn \u0111\u01a1n c\u00f3 \u0111\u1ed9 d\u00e0i b\u1eb1ng l. Trong kho\u1ea3ng th\u1eddi gian \u0394t n\u00f3 th\u1ef1c hi\u1ec7n 5 dao \u0111\u1ed9ng. N\u1ebfu gi\u1ea3m b\u1edbt \u0111\u1ed9 d\u00e0i c\u1ee7a n\u00f3 15 cm th\u00ec trong c\u00f9ng kho\u1ea3ng th\u1eddi gian \u0394t nh\u01b0 tr\u01b0\u1edbc, n\u00f3 th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c 20 dao \u0111\u1ed9ng. Cho g = 9,8 m\/s^{2<\/sup><\/p>\n}

A. l = 16 cm; f \u2248 1,25 Hz. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0B. l = 17 cm; f \u2248 1,21 Hz.<\/p>\n

C. l = 18 cm; f \u2248 1,18 Hz. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0D. l = 20 cm; f \u2248 1,16 Hz.<\/p>\n

C\u00e2u 4:<\/b>\u00a0M\u1ed9t con l\u1eafc \u0111\u01a1n c\u00f3 \u0111\u1ed9 d\u00e0i l dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a t\u1ea1i m\u1ed9t n\u01a1i c\u00f3 gia t\u1ed1c r\u01a1i t\u1ef1 do g, v\u1edbi bi\u00ean \u0111\u1ed9 g\u00f3c \u03b1_{o<\/sub>. Khi v\u1eadt \u0111i qua v\u1ecb tr\u00ed c\u00f3 li \u0111\u1ed9 g\u00f3c \u03b1, n\u00f3 c\u00f3 v\u1eadn t\u1ed1c l\u00e0 v. Khi \u0111\u00f3, bi\u1ec3u th\u1ee9c c\u1ee7a \u03b1o<\/sub>^{2<\/sup>\u00a0c\u00f3 d\u1ea1ng<\/p>\n}}

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C\u00e2u 5:<\/b>\u00a0Ng\u01b0\u1eddi ta ti\u1ebfn h\u00e0nh th\u00ed nghi\u1ec7m \u0111o chu k\u00ec con l\u1eafc \u0111\u01a1n c\u00f3 chi\u1ec1u d\u00e0i 1 m t\u1ea1i m\u1ed9t n\u01a1i tr\u00ean Tr\u00e1i \u0110\u1ea5t. Khi cho con l\u1eafc th\u1ef1c hi\u1ec7n 10 dao \u0111\u1ed9ng m\u1ea5t 20 s (l\u1ea5y \u03c0 = 3,14). Chu k\u00ec dao \u0111\u1ed9ng c\u1ee7a con l\u1eafc v\u00e0 gia t\u1ed1c tr\u1ecdng tr\u01b0\u1eddng c\u1ee7a Tr\u00e1i \u0110\u1ea5t t\u1ea1i n\u01a1i l\u00e0m th\u00ed nghi\u1ec7m l\u00e0<\/p>\n

A. 4 s; 9,86 m\/s^{2<\/sup>. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0B. 2 s; 9,96 m\/s2<\/sup>.<\/p>\n}

C. 4s; 9,96 m\/s^{2<\/sup>. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0D. 2 s; 9,86 m\/s2<\/sup>.<\/p>\n}

C\u00e2u 6:<\/b>\u00a0M\u1ed9t con l\u1eafc \u0111\u01a1n c\u00f3 chi\u1ec1u d\u00e0i l = 1 m, dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a \u1edf n\u01a1i c\u00f3 gia t\u1ed1c tr\u1ecdng tr\u01b0\u1eddng g = \u03c0^{2<\/sup>\u00a0= 10 m\/s2<\/sup>. L\u00fac t = 0, con l\u1eafc \u0111i qua v\u1ecb tr\u00ed c\u00e2n b\u1eb1ng theo chi\u1ec1u d\u01b0\u01a1ng v\u1edbi v\u1eadn t\u1ed1c 0,5 m\/s. Sau 2,5 s v\u1eadn t\u1ed1c c\u1ee7a con l\u1eafc c\u00f3 \u0111\u1ed9 l\u1edbn l\u00e0<\/p>\n}

A. 0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0B. 0,125 m\/s \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0C. 0,5 m\/s \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0D. 0,25 m\/s.<\/p>\n

C\u00e2u 7:<\/b>\u00a0M\u1ed9t con l\u1eafc \u0111\u01a1n m\u1ed7i ng\u00e0y ch\u1ea1y ch\u1eadm 1,5 ph\u00fat. C\u1ea7n ph\u1ea3i \u0111i\u1ec1u ch\u1ec9nh chi\u1ec1u d\u00e0i con l\u1eafc nh\u01b0 th\u1ebf n\u00e0o \u0111\u1ec3 \u0111\u1ed3ng h\u1ed3 ch\u1ea1y \u0111\u00fang?<\/p>\n

A. Gi\u1ea3m chi\u1ec1u d\u00e0i 0,21% \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0B. T\u0103ng chi\u1ec1u d\u00e0i 0,21 %<\/p>\n

C. T\u0103ng chi\u1ec1u d\u00e0i 0,42% \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0D. Gi\u1ea3m chi\u1ec1u d\u00e0i 0,42%.<\/p>\n

C\u00e2u 8:<\/b>\u00a0Hai con l\u1eafc \u0111\u01a1n dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a t\u1ea1i c\u00f9ng m\u1ed9t n\u01a1i tr\u00ean Tr\u00e1i \u0110\u1ea5t, c\u00f3 n\u0103ng l\u01b0\u1ee3ng dao \u0111\u1ed9ng b\u1eb1ng nhau. Qu\u1ea3 n\u1eb7ng c\u1ee7a ch\u00fang c\u00f3 c\u00f9ng kh\u1ed1i l\u01b0\u1ee3ng. Chi\u1ec1u d\u00e0i d\u00e2y treo con l\u1eafc th\u1ee9 nh\u00e2t g\u1ea5p \u0111\u00f4i chi\u1ec1u d\u00e0i d\u00e2y treo con l\u1eafc th\u1ee9 hai. Gi\u1eefa c\u00e1c bi\u00ean \u0111\u1ed9 g\u00f3c c\u1ee7a hai con l\u1eafc c\u00f3 m\u1ed1i li\u00ean h\u1ec7 sau<\/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	B<\/td>\n	C<\/td>\n	A<\/td>\n	C<\/td>\n	D<\/td>\n	A<\/td>\n	A<\/td>\n	D<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n C\u00e2u 2:<\/b>\u00a0C<\/p>\n <\/p>\n C\u00e2u 3:<\/b>\u00a0A<\/p>\n <\/p>\n C\u00e2u 4:<\/b>\u00a0C<\/p>\n <\/p>\n C\u00e2u 5:<\/b>\u00a0D<\/p>\n <\/p>\n C\u00e2u 6:<\/b>\u00a0A<\/p>\n Ph\u01b0\u01a1ng tr\u00ecnh v\u1eadn t\u1ed1c : v = 0,5cos\u03c0t (m\/s)<\/p>\n Sau 2,5 s v\u1eadn t\u1ed1c c\u1ee7a con l\u1eafc l\u00e0 : v = 0,5cos(2,5\u03c0t) = 0<\/p>\n C\u00e2u 7:<\/b>\u00a0A<\/p>\n <\/p>\n C\u00e2u 8:<\/b>\u00a0D<\/p>\n <\/p>\n","protected":false},"excerpt":{"rendered":" C\u00e2u 1:\u00a0T\u1ea1i c\u00f9ng m\u1ed9t v\u1ecb tr\u00ed \u0111\u1ecba l\u00ed, n\u1ebfu \u0111\u1ed9 d\u00e0i con l\u1eafc \u0111\u01a1n t\u0103ng 6,25 l\u1ea7n, th\u00ec s\u1ed1 dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u1ee7a n\u00f3 A. t\u0103ng 2 l\u1ea7n. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0B. gi\u1ea3m 2,5 l\u1ea7n. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0C. gi\u1ea3m 1,5 l\u1ea7n. \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0D. t\u0103ng 4 l\u1ea7n. C\u00e2u 2:\u00a0C\u00f3 hai con l\u1eafc \u0111\u01a1n m\u00e0 \u0111\u1ed9 d\u00e0i c\u1ee7a ch\u00fang h\u01a1n k\u00e9m nhau […]<\/p>\n","protected":false},"author":3,"featured_media":26357,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_mi_skip_tracking":false,"tdm_status":"","tdm_grid_status":""},"categories":[158],"tags":[1445,1444],"yoast_head":"\n