SÁCH CHUYÊN ĐỀ VẬT LÝ 12 - 1

["CH\u01af\u01a0NG 1: DAO \u0110\u1ed8NG \u0110I\u1ec0U H\u00d2A - CH\u1ee6 \u0110\u1ec0 4 C\u00e2u 75: Khi n\u00f3i v\u1ec1 dao \u0111\u1ed9ng c\u01a1, ph\u00e1t bi\u1ec3u n\u00e0o sau \u0111\u00e2y l\u00e0 sai: A. Dao \u0111\u1ed9ng c\u1ee7a con l\u1eafc \u0111\u1ed3ng h\u1ed3 l\u00e0 dao \u0111\u1ed9ng duy tr\u00ec. B. Dao \u0111\u1ed9ng c\u01b0\u1ee1ng b\u1ee9c c\u00f3 bi\u00ean \u0111\u1ed9 kh\u00f4ng ph\u1ee5 thu\u1ed9c v\u00e0o bi\u00ean \u0111\u1ed9 c\u1ee7a l\u1ef1c c\u01b0\u1ee1ng b\u1ee9c. C. Dao \u0111\u1ed9ng c\u01b0\u1ee1ng b\u1ee9c c\u00f3 bi\u00ean \u0111\u1ed9 kh\u00f4ng \u0111\u1ed5i v\u00e0 c\u00f3 t\u1ea7n s\u1ed1 b\u1eb1ng t\u1ea7n s\u1ed1 c\u1ee7a l\u1ef1c c\u01b0\u1ee1ng b\u1ee9c. D. Dao \u0111\u1ed9ng t\u1eaft d\u1ea7n c\u00f3 bi\u00ean \u0111\u1ed9 gi\u1ea3m d\u1ea7n theo th\u1eddi gian. C\u00e2u 76: Khi n\u00f3i v\u1ec1 m\u1ed9t h\u1ec7 dao \u0111\u1ed9ng c\u01b0\u1ee1ng b\u1ee9c \u1edf giai \u0111o\u1ea1n \u1ed5n \u0111\u1ecbnh, ph\u00e1t bi\u1ec3u n\u00e0o d\u01b0\u1edbi \u0111\u00e2y l\u00e0 sai: A. T\u1ea7n s\u1ed1 c\u1ee7a h\u1ec7 dao \u0111\u1ed9ng c\u01b0\u1ee1ng b\u1ee9c b\u1eb1ng t\u1ea7n s\u1ed1 c\u1ee7a ngo\u1ea1i l\u1ef1c c\u01b0\u1ee1ng b\u1ee9c. B. T\u1ea7n s\u1ed1 c\u1ee7a h\u1ec7 dao \u0111\u1ed9ng c\u01b0\u1ee1ng b\u1ee9c lu\u00f4n b\u1eb1ng t\u1ea7n s\u1ed1 dao \u0111\u1ed9ng ri\u00eang c\u1ee7a h\u1ec7. C. Bi\u00ean \u0111\u1ed9 c\u1ee7a dao \u0111\u1ed9ng c\u01b0\u1ee1ng b\u1ee9c ph\u1ee5 thu\u1ed9c v\u00e0o t\u1ea7n s\u1ed1 ngo\u1ea1i l\u1ef1c c\u01b0\u1ee1ng b\u1ee9c. D. Bi\u00ean \u0111\u1ed9 c\u1ee7a h\u1ec7 dao \u0111\u1ed9ng c\u01b0\u1ee1ng b\u1ee9c ph\u1ee5 thu\u1ed9c v\u00e0o bi\u00ean \u0111\u1ed9 ngo\u1ea1i l\u1ef1c c\u01b0\u1ee1ng b\u1ee9c. C\u00e2u 77: Khi n\u00f3i v\u1ec1 dao \u0111\u1ed9ng c\u01a1 c\u01b0\u1ee1ng b\u1ee9c, ph\u00e1t bi\u1ec3u n\u00e0o sau \u0111\u00e2y l\u00e0 sai: A. Bi\u00ean \u0111\u1ed9 c\u1ee7a dao \u0111\u1ed9ng c\u01b0\u1ee1ng b\u1ee9c ph\u1ee5 thu\u1ed9c v\u00e0o bi\u00ean \u0111\u1ed9 c\u1ee7a l\u1ef1c c\u01b0\u1ee1ng b\u1ee9c. B. Bi\u00ean \u0111\u1ed9 c\u1ee7a dao \u0111\u1ed9ng c\u01b0\u1ee1ng b\u1ee9c ph\u1ee5 thu\u1ed9c v\u00e0o t\u1ea7n s\u1ed1 c\u1ee7a l\u1ef1c c\u01b0\u1ee1ng b\u1ee9c. C. Dao \u0111\u1ed9ng c\u01b0\u1ee1ng b\u1ee9c c\u00f3 t\u1ea7n s\u1ed1 lu\u00f4n b\u1eb1ng t\u1ea7n s\u1ed1 c\u1ee7a l\u1ef1c c\u01b0\u1ee1ng b\u1ee9c. D. Dao \u0111\u1ed9ng c\u01b0\u1ee1ng b\u1ee9c c\u00f3 t\u1ea7n s\u1ed1 lu\u00f4n b\u1eb1ng t\u1ea7n s\u1ed1 ri\u00eang c\u1ee7a h\u1ec7. C\u00e2u 78: Bi\u00ean \u0111\u1ed9 c\u1ee7a dao \u0111\u1ed9ng c\u01b0\u1ee1ng b\u1ee9c kh\u00f4ng ph\u1ee5 thu\u1ed9c v\u00e0o: A. Bi\u00ean \u0111\u1ed9 c\u1ee7a ngo\u1ea1i l\u1ef1c. B. L\u1ef1c c\u1ea3n c\u1ee7a m\u00f4i tr\u01b0\u1eddng C. \u0110\u1ed9 ch\u00eanh l\u1ec7ch gi\u1eefa t\u1ea5n s\u1ed1 c\u1ee7a ngo\u1ea1i l\u1ef1c v\u00e0 t\u1ea7n s\u1ed1 ri\u00eang c\u1ee7a h\u1ec7. D. Pha ban \u0111\u1ea7u c\u1ee7 ngo\u1ea1i l\u1ef1c C\u00e2u 79: M\u1ed9t con l\u1eafc l\u00f2 xo g\u1ed3m v\u1eadt kh\u1ed1i l\u01b0\u1ee3ng m = 100 g, l\u00f2 xo c\u00f3 \u0111\u1ed9 c\u1ee9ng k = 100 N\/m. Trong c\u00f9ng m\u1ed9t \u0111i\u1ec1u ki\u1ec7n v\u1ec1 l\u1ef1c c\u1ea3n c\u1ee7a m\u00f4i tr\u01b0\u1eddng th\u00ec bi\u1ec3u th\u1ee9c ngo\u1ea1i l\u1ef1c tu\u1ea7n ho\u00e0n n\u00e0o sau \u0111\u00e2y l\u00e0m cho con l\u1eafc dao \u0111\u1ed9ng c\u01b0\u1ee1ng b\u1ee9c v\u1edbi bi\u00ean \u0111\u1ed9 l\u1edbn nh\u1ea5t? (cho g = 10 m\/s2,\u03c02 = 10). A. F = F0cos(2\u03c0t + 7t) N. B. F = F0cos(20\u03c0t + \u03c0\/2) N. C. F = F0cos(10\u03c0t) N. D. F = F0cos(8\u03c0t) N. C\u00e2u 80: M\u1ed9t chi\u1ebfc xe ch\u1ea1y tr\u00ean con \u0111\u01b0\u1eddng l\u00e1t g\u1ea1ch, c\u1ee9 sau 15m tr\u00ean \u0111\u01b0\u1eddng l\u1ea1i c\u00f3 m\u1ed9t r\u00e3nh nh\u1ecf. Bi\u1ebft chu k\u00ec dao \u0111\u1ed9ng ri\u00eang c\u1ee7a khung xe tr\u00ean c\u00e1c l\u00f2 xo gi\u1ea3m x\u00f3c l\u00e0 1,5s. H\u1ecfi v\u1eadn t\u1ed1c xe b\u1eb1ng bao nhi\u00eau th\u00ec xe b\u1ecb x\u00f3c m\u1ea1nh nh\u1ea5t A. 54km\/h B. 27km\/h C. 34km\/h D. 36km\/h C\u00e2u 81: M\u1ed9t ng\u01b0\u1eddi x\u00e1ch 1 x\u00f4 n\u01b0\u1edbc tr\u00ean \u0111\u01b0\u1eddng, m\u1ed7i b\u01b0\u1edbc ch\u00e2n \u0111i \u0111\u01b0\u1ee3c 50cm, chu k\u00ec dao \u0111\u1ed9ng c\u1ee7a n\u01b0\u1edbc trong x\u00f4 l\u00e0 1s, \u0111\u1ec3 n\u01b0\u1edbc trong x\u00f4 s\u00f3ng s\u00e1nh m\u1ea1nh nh\u1ea5t th\u00ec ng\u01b0\u1eddi \u0111\u00f3 ph\u1ea3i \u0111i v\u1edbi v\u1eadn t\u1ed1c A. 100cm\/s B. 75cm\/s C. 50cm\/s D. 25cm\/s C\u00e2u 82: M\u1ed9t con l\u1eafc \u0111\u01a1n c\u00f3 \u0111\u1ed9 d\u00e0i l=16cm \u0111\u01b0\u1ee3c treo trong toa t\u00e0u \u1edf ngay v\u1ecb tr\u00ed ph\u00eda treen c\u1ee7a tr\u1ee5c b\u00e1nh xe. Chi\u1ec1u d\u00e0i m\u1ed7i thanh ray l\u00e0 12m. L\u1ea5y g=10m\/s2 v\u00e0 \u03c02=10, coi t\u00e0u chuy\u1ec3n \u0111\u1ed9ng th\u1eb3ng \u0111\u1ec1u. Con l\u1eafc s\u1ebd dao \u0111\u1ed9ng m\u1ea1nh nh\u1ea5t khi v\u1eadn t\u1ed1c \u0111o\u00e0n t\u00e0u l\u00e0: A. 15m\/s B. 1,5cm\/s C. 1,5m\/s D. 15cm\/s C\u00e2u 83: M\u1ed9t con l\u1eafc \u0111\u01a1n d\u00e0i 0,3 m \u0111\u01b0\u1ee3c treo v\u00e0o tr\u1ea7n c\u1ee7a m\u1ed9t toa xe l\u1eeda. Con l\u1eafc b\u1ecb k\u00edch \u0111\u1ed9ng m\u1ed7i khi b\u00e1nh xe c\u1ee7a toa xe g\u1eb7p ch\u1ed7 n\u1ed1i nhau c\u1ee7a c\u00e1c \u0111o\u1ea1n \u0111\u01b0\u1eddng ray. Bi\u1ebft chi\u1ec1u d\u00e0i m\u1ed7i thanh ray l\u00e0 12,5 (m) v\u00e0 l\u1ea5y gia t\u1ed1c tr\u1ecdng tr\u01b0\u1eddng 9,8 m\/s2. H\u1ecfi t\u1ea7u ch\u1ea1y v\u1edbi t\u1ed1c \u0111\u1ed9 bao nhi\u00eau th\u00ec bi\u00ean \u0111\u1ed9 c\u1ee7a con l\u1eafc l\u1edbn nh\u1ea5t? A. 60 (km\/h). B. 11,4 (km\/h). C. 41 (km\/h). D. 12,5 (km\/h). TRANG 99","CH\u01af\u01a0NG 1: DAO \u0110\u1ed8NG \u0110I\u1ec0U H\u00d2A - CH\u1ee6 \u0110\u1ec0 4 C\u00e2u 84: M\u1ed9t con l\u1eafc l\u00f2 xo g\u1ed3m v\u1eadt n\u1eb7ng c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng m=100g, l\u00f2 xo c\u00f3 \u0111\u1ed9ng c\u1ee9ng 40N\/m. T\u00e1c \u0111\u1ed9ng v\u00e0o v\u1eadt m\u1ed9t l\u1ef1c tu\u1ea7n ho\u00e0n bi\u00ean \u0111\u1ed9 Fo v\u00e0 t\u1ea7n s\u1ed1 f1=4Hz th\u00ec bi\u00ean \u0111\u1ed9 dao \u0111\u1ed9ng \u1ed5n \u0111\u1ecbnh c\u1ee7a h\u1ec7 l\u00e0 A1. N\u1ebfu gi\u1eef nguy\u00ean bi\u00ean \u0111\u1ed9 Fo v\u00e0 t\u0103ng t\u1ea7n s\u1ed1 \u0111\u1ebfn gi\u00e1 tr\u1ecb f2=5Hz th\u00ec bi\u00ean \u0111\u1ed9 dao \u0111\u1ed9ng l\u00e0 A2. Ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang A. A2 > A1 B. A2 = A1 C. A2 < A1 D. A2 \uf0b3 A1 C\u00e2u 85: M\u1ed9t con l\u1eafc l\u00f2 xo g\u1ed3m vi\u00ean bi nh\u1ecf kh\u1ed1i l\u01b0\u1ee3ng m=250g v\u00e0 l\u00f2 xo kh\u1ed1i l\u01b0\u1ee3ng kh\u00f4ng \u0111\u00e1ng k\u1ec3 c\u00f3 \u0111\u1ed9 c\u1ee9ng K=100N\/m. Con l\u1eafc dao \u0111\u1ed9ng c\u01b0\u1ee1ng b\u1ee9c theo ph\u01b0\u01a1ng tr\u00f9ng v\u1edbi tr\u1ee5c c\u1ee7a l\u00f2 xo d\u01b0\u1edbi t\u00e1c d\u1ee5ng c\u1ee7a ngo\u1ea1i l\u1ef1c tu\u1ea7n ho\u00e0n F=Focoswt(N). Khi thay \u0111\u1ed5i w th\u00ec bi\u00ean \u0111\u1ed9 dao \u0111\u1ed9ng c\u1ee7a vi\u00ean bi thay \u0111\u1ed5i. Khi w l\u1ea7n l\u01b0\u1ee3t l\u00e0 10rad\/s v\u00e0 15rad\/s th\u00ec bi\u00ean \u0111\u1ed9 dao \u0111\u1ed9ng c\u1ee7a vi\u00ean b\u1ecb t\u01b0\u01a1ng \u1ee9ng l\u00e0 A1 v\u00e0 A2. So s\u00e1nh A1 v\u00e0 A2: A. A1=1,5A2 B. A1=A2 C. A1<A2 D. A1>A2 C\u00e2u 86: Con l\u1eafc l\u00f2 xo c\u00f3 t\u1ea7n s\u1ed1 dao \u0111\u1ed9ng ri\u00eang l\u00e0 fo. T\u00e1c d\u1ee5ng m\u1ed9t ngo\u1ea1i l\u1ef1c c\u01b0\u1ee1ng b\u1ee9c bi\u1ebfn thi\u00ean tu\u1ea7n ho\u00e0n bi\u00ean \u0111\u1ed9 Fo v\u00e0 t\u1ea7n s\u1ed1 f1 th\u00ec bi\u00ean \u0111\u1ed9 dao \u0111\u1ed9ng \u1ed5n \u0111\u1ecbnh l\u00e0 A. Khi gi\u1eef nguy\u00ean Fo m\u00e0 t\u0103ng d\u1ea7n t\u1ea7n s\u1ed1 \u0111\u1ebfn f2 th\u00ec th\u1ea5y bi\u00ean \u0111\u1ed9 dao \u0111\u1ed9ng v\u1eabn l\u00e0 A. So s\u00e1nh f1, f2, fo A. f1<fo=f2 B. f1<f2<fo C. f1<fo<f2 D. fo<f1<f B\u1ea2NG \u0110\u00c1P \u00c1N 1.C 2.B 3.B 4.C 5.D 6.A 7.C 8.C 9.D 10.A 11.C 12.A 13.A 14.D 15.D 16.B 17.B 18.B 19.C 20.D 21.C 22.A 23.B 24.B 25.B 26.D 27.A 28.A 29.A 30.C 31.A 32.A 33.A 34.A 35.C 36.A 37.D 38.C 39.C 40.C 41.B 42.D 43.A 44.C 45.C 46.A 47.D 48.D 49.D 50.D 51.A 52.B 53.B 54.D 55.D 56.B 57.B 58.D 59.B 60.A 61.D 62.D 63.A 64.C 65.C 66.A 67.D 68.D 69.A 70.C 71.B 72.A 73.A 74.A 75.B 76.B 77.D 78.D 79.C 80.D 81.C 82.A 83.C 84.C 85.C 86.C QR CODE PDF L\u1eddi gi\u1ea3i TRANG 100","CH\u01af\u01a0NG 1: DAO \u0110\u1ed8NG \u0110I\u1ec0U H\u00d2A - VDC CHUY\u00caN \u0110\u1ec0 N\u00c2NG CAO \u0110\u1ed2 TH\u1eca HAI V\u1eacT DAO \u0110\u1ed8NG \u0110I\u1ec0U H\u00d2A CHUY\u00caN \u0110\u1ec0 N\u00c2NG CAO PH\u1ea6N 1: \u0110\u1ed2 TH\u1eca C\u1ee6A HAI V\u1eacT DAO \u0110\u1ed8NG \u0110I\u1ec0U H\u00d2A TRANG 101","CH\u01af\u01a0NG 1: DAO \u0110\u1ed8NG \u0110I\u1ec0U H\u00d2A - VDC C\u00e2u 1: (Minh H\u1ecda-2018) Dao \u0111\u1ed9ng c\u1ee7a m\u1ed9t v\u1eadt c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng 200g l\u00e0 t\u1ed5ng h\u1ee3p c\u1ee7a hai dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u00f9ng ph\u01b0\u01a1ng D1 v\u00e0 D2. H\u00ecnh v\u1ebd b\u00ean l\u00e0 \u0111\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n s\u1ef1 ph\u1ee5 thu\u1ed9c c\u1ee7a li \u0111\u1ed9 c\u1ee7a D1 v\u00e0 D2 theo th\u1eddi gian. M\u1ed1c th\u1ebf n\u0103ng t\u1ea1i v\u1ecb tr\u00ed c\u00e2n b\u1eb1ng c\u1ee7a v\u1eadt. Bi\u1ebft c\u01a1 n\u0103ng c\u1ee7a v\u1eadt l\u00e0 22,5 mJ. L\u1ea5y \u03c02=10 Bi\u00ean \u0111\u1ed9 dao \u0111\u1ed9ng D2 c\u00f3 gi\u00e1 tr\u1ecb c\u00f3 gi\u00e1 tr\u1ecb g\u1ea7n nh\u1ea5t v\u1edbi gi\u00e1 tr\u1ecb n\u00e0o sau \u0111\u00e2y: A. 5,2 cm B. 5,4cm C. 4,8cm D. 5,7cm C\u00e2u 2: (VDC - \u0110H2021) Dao \u0111\u1ed9ng c\u1ee7a m\u1ed9t v\u1eadt l\u00e0 t\u1ed5ng h\u1ee3p c\u1ee7a hai dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u00f9ng ph\u01b0\u01a1ng c\u00f3 li \u0111\u1ed9 l\u1ea7n l\u01b0\u1ee3t l\u00e0 x1 v\u00e0 x2. H\u00ecnh b\u00ean l\u00e0 \u0111\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n s\u1ef1 ph\u1ee5 thu\u1ed9c c\u1ee7a x1 v\u00e0 x2 theo th\u1eddi gian t. Bi\u1ebft \u0111\u1ed9 l\u1edbn l\u1ef1c k\u00e9o v\u1ec1 t\u00e1c d\u1ee5ng l\u00ean v\u1eadt \u1edf th\u1eddi \u0111i\u1ec3m t = 0,2 s l\u00e0 0,4 N. \u0110\u1ed9ng n\u0103ng c\u1ee7a v\u1eadt \u1edf th\u1eddi \u0111i\u1ec3m t = 0,4 s l\u00e0: A. 15,6 mJ. B. 6,4 mJ. C. 11,2 mJ. D. 4,8 mJ. TRANG 102","CH\u01af\u01a0NG 1: DAO \u0110\u1ed8NG \u0110I\u1ec0U H\u00d2A - VDC C\u00e2u 3: (VDC- \u0110H2020) Hai v\u1eadt A v\u00e0 B dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u00f9ng t\u1ea7n s\u1ed1. H\u00ecnh b\u00ean l\u00e0 \u0111\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n s\u1ef1 ph\u1ee5 thu\u1ed9c c\u1ee7a li \u0111\u1ed9 x1 c\u1ee7a A v\u00e0 x2 c\u1ee7a B theo th\u1eddi gian. Hai dao \u0111\u1ed9ng c\u1ee7a A v\u00e0 B l\u1ec7ch pha nhau A. 0,2 rad B. 1,7 rad C. 1,65 rad D. 1,49 rad C\u00e2u 4: (VDC - \u0110H2018)Hai v\u1eadt M1 v\u00e0 M2 dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u00f9ng t\u1ea7n s\u1ed1. H\u00ecnh b\u00ean l\u00e0 \u0111\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n s\u1ef1 ph\u1ee5 thu\u1ed9c c\u1ee7a li \u0111\u1ed9 x1 c\u1ee7a M1 v\u00e0 v\u1eadn t\u1ed1c v2 c\u1ee7a M2 theo th\u1eddi gian t. Hai dao \u0111\u1ed9ng c\u1ee7a M1 v\u00e0 M2 l\u1ec7ch pha nhau \uf070 B. 2\uf070 A. 3 3 5\uf070 \uf070 C. D. 6 6 TRANG 103","CH\u01af\u01a0NG 1: DAO \u0110\u1ed8NG \u0110I\u1ec0U H\u00d2A - VDC B\u00c0I T\u1eacP T\u1ef0 LUY\u1ec6N C\u00e2u 5: \u0110\u1ed3 th\u1ecb c\u1ee7a hai dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u00f9ng t\u1ea7n s\u1ed1 \u0111\u01b0\u1ee3c v\u1ebd nh\u01b0 sau: Ph\u01b0\u01a1ng tr\u00ecnh dao \u0111\u1ed9ng t\u1ed5ng h\u1ee3p c\u1ee7a ch\u00fang l\u00e0 A. x = 5cos \uf070 t cm. B. x = 5cos\uf0e6\uf0e7\uf0e8 \uf070 + \uf070 \uf0f6 cm. 2 t \uf0f7\uf0f8 2 C. x = cos \uf0e6 \uf070 t \u2212 \uf070 \uf0f6 cm D. x = cos \uf0e6 \uf070 t \u2212 \uf070 \uf0f6 cm \uf0e7\uf0e8 2 \uf0f7\uf0f8 \uf0e7\uf0e8 2 2 \uf0f7\uf0f8 C\u00e2u 6: Hai dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u00f9ng t\u1ea7n s\u1ed1 c\u00f3 \u0111\u1ed3 th\u1ecb nh\u01b0 h\u00ecnh v\u1ebd. \u0111\u1ed9 l\u1ec7ch pha c\u1ee7a \u0111ao \u0111\u1ed9ng (1) so v\u1edbi dao \u0111\u1ed9ng (2) l\u00e0 2\uf070 \uf070 A. rad . B. rad . 3 3 \uf070 D. \u2212 \uf070 C. rad . rad . 6 4 C\u00e2u 7: Cho hai ch\u1ea5t \u0111i\u1ec3m dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a tr\u00ean hai \u0111\u01b0\u1eddng th\u1eb3ng song song v\u1edbi nhau v\u00e0 c\u00f9ng song song v\u1edbi tr\u1ee5c Ox. V\u1ecb tr\u00ed c\u00e2n b\u1eb1ng c\u1ee7a hai ch\u1ea5t \u0111i\u1ec3m \u0111\u1ec1u n\u1eb1m tr\u00ean m\u1ed9t \u0111\u01b0\u1eddng th\u1eb3ng qua O v\u00e0 vu\u00f4ng g\u00f3c v\u1edbi tr\u1ee5c Ox. \u0110\u1ed3 th\u1ecb li \u0111\u1ed9 - th\u1eddi gian c\u1ee7a hai ch\u1ea5t \u0111i\u1ec3m \u0111\u01b0\u1ee3c bi\u1ec5u di\u1ec5n nh\u01b0 h\u00ecnh v\u1ebd. Th\u1eddi \u0111i\u1ec3m \u0111\u1ea7u ti\u00ean hai ch\u1ea5t \u0111i\u1ec3m c\u00e1ch xa nhau nh\u1ea5t k\u1ec3 t\u1eeb th\u1eddi \u0111i\u1ec3m ban \u0111\u1ea7u l\u00e0 A. 0,0756 s. B. 0,0656 s. C. 0,0856 s. D. 0,0556 s. C\u00e2u 8: Hai con l\u1eafc l\u00f2 xo gi\u1ed1ng nhau c\u00f3 c\u00f9ng kh\u1ed1i l\u01b0\u1ee3ng v\u1eadt n\u1eb7ng C\u00e2u 9: m v\u00e0 c\u00f9ng \u0111\u1ed9 c\u1ee9ng l\u00f2 xo k. Hai con l\u1eafc dao \u0111\u1ed9ng tr\u00ean hai \u0111\u01b0\u1eddng th\u1eb3ng song song, c\u00f3 v\u1ecb tr\u00ed c\u00e2n b\u1eb1ng \u1edf c\u00f9ng g\u1ed1c t\u1ecda \u0111\u1ed9. Ch\u1ecdn m\u1ed1c th\u1ebf n\u0103ng t\u1ea1i v\u1ecb tr\u00ed c\u00e2n b\u1eb1ng, \u0111\u1ed3 th\u1ecb li \u0111\u1ed9 - th\u1eddi gian c\u1ee7a hai dao \u0111\u1ed9ng \u0111\u01b0\u1ee3c cho nh\u01b0 h\u00ecnh v\u1ebd. \u1ede th\u1eddi \u0111i\u1ec3m t, con l\u1eafc th\u1ee9 nh\u1ea5t c\u00f3 \u0111\u1ed9ng n\u0103ng 0,06 J v\u00e0 con l\u1eafc th\u1ee9 hai c\u00f3 th\u1ebf n\u0103ng 4.10\u22123 J . Kh\u1ed1i l\u01b0\u1ee3ng m l\u00e0 A. 1 kg . B. 3kg . C. 2kg . D. 2 kg . 3 9 6049 Hai ch\u1ea5t \u0111i\u1ec3m dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u00f9ng t\u1ea7n s\u1ed1 tr\u00ean hai D. s \u0111\u01b0\u1eddng th\u1eb3ng song song k\u1ec1 nhau v\u00e0 c\u00f9ng song song v\u1edbi 6 Ox c\u00f3 \u0111\u1ed3 th\u1ecb li \u0111\u1ed9 nh\u01b0 h\u00ecnh v\u1ebd ( kho\u1ea3ng c\u00e1ch gi\u1eefa hai \u0111\u01b0\u1eddng th\u1eb3ng r\u1ea5t nh\u1ecf so v\u1edbi kho\u1ea3ng c\u00e1ch c\u1ee7a hai ch\u1ea5t \u0111i\u1ec3m tr\u00ean tr\u1ee5c Ox). V\u1ecb tr\u00ed c\u00e2n b\u1eb1ng c\u1ee7a hai ch\u1ea5t \u0111i\u1ec3m \u0111\u1ec1u \u1edf tr\u00ean m\u1ed9t \u0111\u01b0\u1eddng th\u1eb3ng qua g\u1ed1c t\u1ecda \u0111\u1ed9 v\u00e0 vu\u00f4ng g\u00f3c v\u1edbi Ox. Bi\u1ebft t2 \u2212 t1 = 3s . K\u1ec3 t\u1eeb l\u00fac t = 0, hai ch\u1ea5t \u0111i\u1ec3m c\u00e1ch nhau 5 3 cm l\u1ea7n th\u1ee9 2017 12097 6047 12097 A. s. B. s . C. s. 6 6 12 TRANG 104","CH\u01af\u01a0NG 1: DAO \u0110\u1ed8NG \u0110I\u1ec0U H\u00d2A - VDC C\u00e2u 10: (VDC - \u0110H2021) Dao \u0111\u1ed9ng c\u1ee7a m\u1ed9t v\u1eadt l\u00e0 t\u1ed5ng h\u1ee3p c\u1ee7a hai dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u00f9ng ph\u01b0\u01a1ng c\u00f3 li \u0111\u1ed9 l\u1ea7n l\u01b0\u1ee3t l\u00e0 x1 v\u00e0 x2. H\u00ecnh b\u00ean l\u00e0 \u0111\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n s\u1ef1 ph\u1ee5 thu\u1ed9c c\u1ee7a x1 v\u00e0 x2 theo th\u1eddi gian t. Bi\u1ebft \u0111\u1ed9 l\u1edbn l\u1ef1c k\u00e9o v\u1ec1 t\u00e1c d\u1ee5ng l\u00ean v\u1eadt \u1edf th\u1eddi \u0111i\u1ec3m t = 0,2 s l\u00e0 0,5 N. \u0110\u1ed9ng n\u0103ng c\u1ee7a v\u1eadt \u1edf th\u1eddi \u0111i\u1ec3m t = 0,4 s l\u00e0 A. 14 mJ. B. 24 mJ. C. 8 mJ. D. 6 mJ. C\u00e2u 11: (VDC- \u0110H2021) Dao \u0111\u1ed9ng c\u1ee7a m\u1ed9t v\u1eadt l\u00e0 t\u1ed5ng h\u1ee3p c\u1ee7a hai dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u00f9ng ph\u01b0\u01a1ng c\u00f3 li \u0111\u1ed9 l\u1ea7n l\u01b0\u1ee3t l\u00e0 x1 v\u00e0 x2. H\u00ecnh b\u00ean l\u00e0 \u0111\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n s\u1ef1 ph\u1ee5 thu\u1ed9c c\u1ee7a x1 v\u00e0 x2 theo th\u1eddi gian t. Bi\u1ebft \u0111\u1ed9 l\u1edbn l\u1ef1c k\u00e9o v\u1ec1 t\u00e1c d\u1ee5ng l\u00ean v\u1eadt \u1edf th\u1eddi \u0111i\u1ec3m t = 0,4 s l\u00e0 0,4 N. \u0110\u1ed9ng n\u0103ng c\u1ee7a v\u1eadt \u1edf th\u1eddi \u0111i\u1ec3m t = 0,8 s l\u00e0: A. 12,5 mJ. B. 14,0 mJ. C. 1,5 mJ. D. 19,5 mJ. C\u00e2u 12: (VDC- \u0110H2020) Hai v\u1eadt A v\u00e0 B dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u00f9ng t\u1ea7n s\u1ed1. H\u00ecnh b\u00ean l\u00e0 \u0111\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n s\u1ef1 ph\u1ee5 thu\u1ed9c c\u1ee7a li \u0111\u1ed9 x1 c\u1ee7a A v\u00e0 x2 c\u1ee7a B theo th\u1eddi gian. Hai dao \u0111\u1ed9ng c\u1ee7a A v\u00e0 B l\u1ec7ch pha nhau A. 1,49 rad B. 1,7 rad C. 0,2 rad D. 1,65 rad C\u00e2u 13: (VDC - \u0110H2018) Hai v\u1eadt M1 v\u00e0 M2 dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u00f9ng t\u1ea7n s\u1ed1. H\u00ecnh b\u00ean l\u00e0 \u0111\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n s\u1ef1 ph\u1ee5 thu\u1ed9c c\u1ee7a li \u0111\u1ed9 x1 c\u1ee7a M1 v\u00e0 v\u1eadn t\u1ed1c v2 c\u1ee7a M2 theo th\u1eddi gian t. Hai dao \u0111\u1ed9ng c\u1ee7a M1 v\u00e0 M2 l\u1ec7ch pha nhau A. 5\uf070 \uf070 6 B. 6 \uf070 2\uf070 C. D. 3 3 C\u00e2u 14: (VDC - \u0110H2018)Hai v\u1eadt M1 v\u00e0 M2 dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u00f9ng t\u1ea7n s\u1ed1. H\u00ecnh b\u00ean l\u00e0 \u0111\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n s\u1ef1 ph\u1ee5 thu\u1ed9c c\u1ee7a li \u0111\u1ed9 x1 c\u1ee7a M1 v\u00e0 v\u1eadn t\u1ed1c v2 c\u1ee7a M2 theo th\u1eddi gian t. Hai dao \u0111\u1ed9ng c\u1ee7a M1 v\u00e0 M2 l\u1ec7ch pha nhau 5\uf070 \uf070\uf070 2\uf070 A. B. C. D. 6 63 3 C\u00e2u 15: (VDC -\u0110H2018)Hai v\u1eadt M1 v\u00e0 M2 dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u00f9ng t\u1ea7n s\u1ed1. H\u00ecnh b\u00ean l\u00e0 \u0111\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n s\u1ef1 ph\u1ee5 thu\u1ed9c c\u1ee7a li \u0111\u1ed9 x1 c\u1ee7a M1 v\u00e0 v\u1eadn t\u1ed1c v2 c\u1ee7a M2 theo th\u1eddi gian t. Hai dao \u0111\u1ed9ng c\u1ee7a M1 v\u00e0 M2 l\u1ec7ch pha nhau A. 5\uf070 \uf070 \uf070 D. 2\uf070 B. C. 3 6 63 TRANG 105","CH\u01af\u01a0NG 1: DAO \u0110\u1ed8NG \u0110I\u1ec0U H\u00d2A - VDC B\u1ea2NG \u0110\u00c1P \u00c1N 1.A 2.D 3.C 4.D 5.D 6.B 7.B 8.B 9.D 10.D 11.C 12.D 13.A 14.B 15.A 16.B 17.B 18.B 19.C 20.D QR CODE PDF L\u1eddi gi\u1ea3i TRANG 106","CH\u01af\u01a0NG 7: H\u1ea0T NH\u00c2N NGUY\u00caN T\u1eec \u2013 CH\u1ee6 \u0110\u1ec0 4 CHUY\u00caN \u0110\u1ec0 N\u00c2NG CAO \u0110\u1ed2 TH\u1eca L\u1ef0C \u0110\u00c0N H\u1ed2I PH\u1ea6N 2: CHUY\u00caN \u0110\u1ec0 N\u00c2NG CAO \u0110\u1ed2 TH\u1eca L\u1ef0C \u0110\u00c0N H\u1ed2I TRANG 107","CH\u01af\u01a0NG 7: H\u1ea0T NH\u00c2N NGUY\u00caN T\u1eec \u2013 CH\u1ee6 \u0110\u1ec0 4 C\u00e2u 1: M\u1ed9t con l\u1eafc l\u00f2 xo treo th\u1eb3ng \u0111\u1ee9ng c\u00f3 \u0111\u1ed9 c\u1ee9ng k = 25 N\/m dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a theo ph\u01b0\u01a1ng th\u1eb3ng \u0111\u1ee9ng. Bi\u1ebft tr\u1ee5c Ox th\u1eb3ng \u0111\u1ee9ng h\u01b0\u1edbng xu\u1ed1ng, g\u1ed1c O tr\u00f9ng v\u1edbi v\u1ecb tr\u00ed c\u00e2n b\u1eb1ng. Bi\u1ebft gi\u00e1 tr\u1ecb \u0111\u1ea1i s\u1ed1 c\u1ee7a l\u1ef1c \u0111\u00e0n h\u1ed3i t\u00e1c d\u1ee5ng l\u00ean v\u1eadt bi\u1ebfn thi\u00ean theo \u0111\u1ed3 th\u1ecb. Vi\u1ebft ph\u01b0\u01a1ng tr\u00ecnh dao \u0111\u1ed9ng c\u1ee7a v\u1eadt? A. x = 8cos \uf0e6 4\uf070t + \uf070 \uf0f6 cm.B. x = 10cos\uf0e6\uf0e7\uf0e85\uf070t + \uf070 \uf0f6 cm. \uf0e7\uf0e8 3 \uf0f7\uf0f8 3 \uf0f7\uf0f8 C. x = 8cos\uf0e6\uf0e7\uf0e8 4\uf070t \u2212 \uf070 \uf0f6 cm.D. x = 10 cos \uf0e6 5\uf070t \u2212 2\uf070 \uf0f6 cm. 3 \uf0f7\uf0f8 \uf0e7\uf0e8 3 \uf0f7\uf0f8 C\u00e2u 2: (Minh H\u1ecda-2020) M\u1ed9t con l\u1eafc l\u00f2 xo \u0111\u01b0\u1ee3c treo v\u00e0o m\u1ed9t \u0111i\u1ec3m M c\u1ed1 \u0111\u1ecbnh, \u0111ang dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a theo ph\u01b0\u01a1ng th\u1eb3ng \u0111\u1ee9ng. H\u00ecnh v\u1ebd b\u00ean l\u00e0 \u0111\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n s\u1ef1 ph\u1ee5 thu\u1ed9c c\u1ee7a l\u1ef1c \u0111\u00e0n h\u1ed3i F\u0111h m\u00e0 l\u00f2 xo t\u00e1c d\u1ee5ng v\u00e0o \u0111i\u1ec3m M theo theo gian t. L\u1ea5y g=\u03c02=10 m\/s2. \u0110\u1ed9 d\u00e3n c\u1ee7a l\u00f2 xo khi con l\u1eafc \u1edf v\u1ecb tr\u00ed c\u00e2n b\u1eb1ng l\u00e0: A. 2 cm B. 4 cm C. 6 cm D. 8 cm TRANG 108","CH\u01af\u01a0NG 7: H\u1ea0T NH\u00c2N NGUY\u00caN T\u1eec \u2013 CH\u1ee6 \u0110\u1ec0 4 C\u00e2u 3: (VDC- \u0110H2019) M\u1ed9t con l\u1eafc l\u00f2 xo \u0111\u01b0\u1ee3c treo v\u00e0o m\u1ed9t \u0111i\u1ec3m c\u1ed1 \u0111\u1ecbnh \u0111ang dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a theo ph\u01b0\u01a1ng th\u1eb3ng \u0111\u1ee9ng. H\u00ecnh b\u00ean l\u00e0 \u0111\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n s\u1ef1 ph\u1ee5 thu\u1ed9c c\u1ee7a l\u1ef1c \u0111\u00e0n h\u1ed3i F m\u00e0 l\u00f2 xo t\u00e1c d\u1ee5ng l\u00ean v\u1eadt nh\u1ecf c\u1ee7a con l\u1eafc theo th\u1eddi gian t. T\u1ea1i t=0,3 s, l\u1ef1c k\u00e9o v\u1ec1 t\u00e1c d\u1ee5ng l\u00ean v\u1eadt c\u00f3 \u0111\u1ed9 l\u1edbn l\u00e0 A. 3,5N B. 4,5N C. 1,5N D. 2,5 TRANG 109","CH\u01af\u01a0NG 7: H\u1ea0T NH\u00c2N NGUY\u00caN T\u1eec \u2013 CH\u1ee6 \u0110\u1ec0 4 C\u00e2u 4: (VDC - Minh H\u1ecda -2021) M\u1ed9t con l\u1eafc l\u00f2 xo treo th\u1eb3ng \u0111\u1ee9ng, dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a t\u1ea1i n\u01a1i c\u00f3 g = 10m \/ s2 . H\u00ecnh b\u00ean l\u00e0 \u0111\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n s\u1ef1 ph\u1ee5 thu\u1ed9c c\u1ee7a \u0111\u1ed9 l\u1edbn l\u1ef1c k\u00e9o v\u1ec1 Fkv t\u00e1c d\u1ee5ng l\u00ean v\u1eadt v\u00e0 \u0111\u1ed9 l\u1edbn l\u1ef1c \u0111\u00e0n h\u1ed3i F\u0111h c\u1ee7a l\u00f2 xo theo th\u1eddi gian t. Bi\u1ebft t2 \u2212 t1 = 7\uf070 (s). Khi l\u00f2 xo 120 d\u00e3n 6,5 cm th\u00ec t\u1ed1c \u0111\u1ed9 c\u1ee7a v\u1eadt l\u00e0 A. 80 cm\/s. B. 60 cm\/s. C. 51 cm\/s. D. 110 cm\/s. TRANG 110","CH\u01af\u01a0NG 7: H\u1ea0T NH\u00c2N NGUY\u00caN T\u1eec \u2013 CH\u1ee6 \u0110\u1ec0 4 C\u00e2u 5: (VDC- \u0110H2019) M\u1ed9t con l\u1eafc l\u00f2 xo \u0111\u01b0\u1ee3c treo v\u00e0o m\u1ed9t \u0111i\u1ec3m C\u00e2u 6: c\u1ed1 \u0111\u1ecbnh \u0111ang dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a theo ph\u01b0\u01a1ng th\u1eb3ng \u0111\u1ee9ng. H\u00ecnh b\u00ean l\u00e0 \u0111\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n s\u1ef1 ph\u1ee5 thu\u1ed9c c\u1ee7a l\u1ef1c \u0111\u00e0n h\u1ed3i F m\u00e0 l\u00f2 xo t\u00e1c d\u1ee5ng l\u00ean v\u1eadt nh\u1ecf c\u1ee7a con l\u1eafc theo th\u1eddi gian t. T\u1ea1i t=0,45 s, l\u1ef1c k\u00e9o v\u1ec1 t\u00e1c d\u1ee5ng l\u00ean v\u1eadt c\u00f3 \u0111\u1ed9 l\u1edbn l\u00e0 A. 1,59N B. 1,29N C. 2,29N D. 1,89N Con l\u1eafc l\u00f2 xo treo th\u1eb3ng \u0111\u1ee9ng dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a \u1edf n\u01a1i c\u00f3 gia t\u1ed1c tr\u1ecdng tr\u01b0\u1eddng g = \u03c02 m\/s2. \u0110\u1ed9 l\u1edbn l\u1ef1c \u0111\u00e0n h\u1ed3i c\u1ee7a l\u00f2 xo bi\u1ebfn thi\u00ean theo \u0111\u1ed3 th\u1ecb nh\u01b0 h\u00ecnh v\u1ebd. L\u1ea5y \u03c02 \u2248 10. Kh\u1ed1i l\u01b0\u1ee3ng c\u1ee7a v\u1eadt nh\u1ecf b\u1eb1ng A. 100 g. B. 300 g. C. 200 g. D. 400 g. C\u00e2u 7: Hai con l\u1eafc l\u00f2 xo th\u1eb3ng \u0111\u1ee9ng. Chi\u1ec1u d\u01b0\u01a1ng h\u01b0\u1edbng xu\u1ed1ng, \u0111\u1ed9 C\u00e2u 8: l\u1edbn c\u1ee7a l\u1ef1c \u0111\u00e0n h\u1ed3i t\u00e1c d\u1ee5ng l\u00ean m\u1ed7i con l\u1eafc c\u00f3 \u0111\u1ed3 th\u1ecb ph\u1ee5 thu\u1ed9c v\u00e0o th\u1eddi gian nh\u01b0 h\u00ecnh v\u1ebd. C\u01a1 n\u0103ng c\u1ee7a con l\u1eafc (1) v\u00e0 (2) l\u1ea7n l\u01b0\u1ee3t l\u00e0 W1 v\u00e0 W2. T\u1ec9 s\u1ed1 W1 W2 A. 0,18 B. 0,36 C. 0,54 D. 0,72 (Chuy\u00ean Tr\u1ea7n Ph\u00fa \u2013 2018) M\u1ed9t con l\u1eafc l\u00f2 xo th\u1eb3ng \u0111\u1ee9ng g\u1ed3m m\u1ed9t v\u1eadt nh\u1ecf c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng m = 200 g v\u00e0 l\u00f2 xo c\u00f3 \u0111\u1ed9 c\u1ee9ng k c\u00f3 \u0111\u1ea7u tr\u00ean c\u1ed1 \u0111inh, v\u1eadt \u0111ang dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a theo ph\u01b0\u01a1ng th\u1eb3ng \u0111\u1ee9ng. Ch\u1ecdn g\u1ed1c t\u1ecda \u0111\u1ed9 O \u1edf v\u1ecb tr\u00ed c\u00e2n b\u1eb1ng. Chi\u1ec1u d\u01b0\u01a1ng c\u1ee7a tr\u1ee5c Ox h\u01b0\u1edbng xu\u1ed1ng d\u01b0\u1edbi. \u0110\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n s\u1ef1 ph\u1ee5 thu\u1ed9c c\u1ee7a gi\u00e1 tr\u1ecb \u0111\u1ea1i s\u1ed1 c\u1ee7a l\u1ef1c \u0111\u00e0n h\u1ed3i theo th\u1eddi gian \u0111\u01b0\u1ee3c cho nh\u01b0 h\u00ecnh v\u1ebd. Bi\u1ebft ta c\u00f3 h\u1ec7 th\u1ee9c : F1 + 3F2 + 5F3 = 0. L\u1ea5y g = 10 m\/s2. T\u1ec9 s\u1ed1 th\u1eddi gian l\u00f2 xo gi\u00e3n v\u1edbi th\u1eddi gian l\u00f2 xo n\u00e9n trong m\u1ed9t chu k\u1ef3 dao \u0111\u1ed9ng g\u1ea7n gi\u00e1 tr\u1ecb n\u00e0o nh\u1ea5t sau \u0111\u00e2y ? A. 1,24. B. 1,38. C. 1,30. D. 1,15 TRANG 111","CH\u01af\u01a0NG 7: H\u1ea0T NH\u00c2N NGUY\u00caN T\u1eec \u2013 CH\u1ee6 \u0110\u1ec0 4 B\u1ea2NG \u0110\u00c1P \u00c1N 1.B 2.B 3.D 4.B 5.B 6.C 7.D 8.A QR CODE PDF L\u1eddi gi\u1ea3i TRANG 112","CH\u01af\u01a0NG 7: H\u1ea0T NH\u00c2N NGUY\u00caN T\u1eec \u2013 CH\u1ee6 \u0110\u1ec0 4 CHUY\u00caN \u0110\u1ec0 V\u1eacN D\u1ee4NG CAO HAI V\u1eacT N\u1ed0I NHAU B\u1eb0NG S\u1ee2I D\u00c2Y KH\u00d4NG D\u00c3N PH\u1ea6N 3: HAI V\u1eacT N\u1ed0I NHAU B\u1eb0NG S\u1ee2I D\u00c2Y KH\u00d4NG D\u00c3N \uf0b5 PH\u00c2N T\u00cdCH HI\u1ec6N T\u01af\u1ee2NG V\u1eacT L\u00dd TRANG 113","CH\u01af\u01a0NG 7: H\u1ea0T NH\u00c2N NGUY\u00caN T\u1eec \u2013 CH\u1ee6 \u0110\u1ec0 4 \uf034 V\u00ed D\u1ee5 1: Cho c\u01a1 h\u1ec7 nh\u01b0 h\u00ecnh v\u1ebd. V\u1eadt m1 c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng 1 kg, g\u1eafn v\u1edbi l\u00f2 xo nh\u1eb9 c\u00f3 \u0111\u1ed9 c\u1ee9ng k = 40 N\/m, v\u1eadt m2 c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng 3 kg mang \u0111i\u1ec7n t\u00edch q = 10-4 C n\u1ed1i v\u1edbi m1 b\u1eb1ng m\u1ed9t s\u1ee3i d\u00e2y m\u1ec1m, nh\u1eb9, kh\u00f4ng d\u00e3n, c\u00f3 chi\u1ec1u d\u00e0i l = 15 cm. C\u1ea3 hai v\u1eadt m1 v\u00e0 m2 c\u00f3 th\u1ec3 chuy\u1ec3n \u0111\u1ed9ng t\u1ecbnh ti\u1ebfn kh\u00f4ng ma s\u00e1t tr\u00ean m\u1eb7t ph\u1eb3ng ngang. Ban \u0111\u1ea7u l\u00f2 xo c\u00f3 \u0111\u1ed9 d\u00e0i t\u1ef1 nhi\u00ean, s\u1ee3i d\u00e2y c\u0103ng. Thi\u1ebft l\u1eadp m\u1ed9t \u0111i\u1ec7n tr\u01b0\u1eddng \u0111\u1ec1u c\u00f3 c\u01b0\u1eddng \u0111\u1ed9 \u0111i\u1ec7n tr\u01b0\u1eddng E = 2.104 V\/m h\u01b0\u1edbng t\u1eeb tr\u00e1i s\u00e1ng ph\u1ea3i trong kho\u1ea3ng th\u1eddi gian 0,5 s. L\u1ea5y \u03c02 = 10. Sau khi ng\u1eaft \u0111i\u1ec7n tr\u01b0\u1eddng 1s, kho\u1ea3ng c\u00e1ch gi\u1eefa hai v\u1eadt m1 v\u00e0 m2 l\u00e0 A. 6 cm B. 13 cm C. 9 cm D. 11 cm TRANG 114","CH\u01af\u01a0NG 7: H\u1ea0T NH\u00c2N NGUY\u00caN T\u1eec \u2013 CH\u1ee6 \u0110\u1ec0 4 \uf034 V\u00ed D\u1ee5 2: (\u0110H \u2013 2016) M\u1ed9t l\u00f2 xo nh\u1eb9 c\u00f3 \u0111\u1ed9 c\u1ee9ng 20 N\/m, \u0111\u1ea7u tr\u00ean \u0111\u01b0\u1ee3c treo v\u00e0o m\u1ed9t \u0111i\u1ec3m c\u1ed1 \u0111\u1ecbnh, \u0111\u1ea7u d\u01b0\u1edbi g\u1eafn v\u1edbi v\u1eadt nh\u1ecf A kh\u1ed1i l\u01b0\u1ee3ng 100 g; v\u1eadt A \u0111\u01b0\u1ee3c n\u1ed1i v\u1edbi v\u1eadt nh\u1ecf B c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng 100 g b\u1eb1ng m\u1ed9t s\u1ee3i d\u00e2y m\u1ec1m, m\u00e3nh, nh\u1eb9, kh\u00f4ng d\u00e3n v\u00e0 \u0111\u1ee7 d\u00e0i. T\u1eeb v\u1ecb tr\u00ed c\u00e2n b\u1eb1ng c\u1ee7a h\u1ec7, k\u00e9o v\u1eadt B th\u1eb3ng \u0111\u1ee9ng xu\u1ed1ng d\u01b0\u1edbi m\u1ed9t \u0111o\u1ea1n 20 cm r\u1ed3i th\u1ea3 nh\u1eb9 \u0111\u1ec3 v\u1eadt B di chuy\u1ec3n \u0111i l\u00ean v\u1edbi v\u1eadn t\u1ed1c ban \u0111\u1ea7u b\u1eb1ng kh\u00f4ng. Khi v\u1eadt B b\u1eaft \u0111\u1ea7u \u0111\u1ed5i chi\u1ec1u chuy\u1ec3n \u0111\u1ed9ng th\u00ec b\u1ea5t ng\u1edd b\u1ecb tu\u1ed9t kh\u1ecfi d\u00e2y n\u1ed1i. B\u1ecf qua c\u00e1c l\u1ef1c c\u1ea3n, l\u1ea5y g = 10 m\/s2. Kho\u1ea3ng th\u1eddi gian t\u1eeb khi v\u1eadt B b\u1ecb tu\u1ed9t kh\u1ecfi d\u00e2y n\u1ed1i \u0111\u1ebfn khi r\u01a1i \u0111\u1ebfn v\u1ecb tr\u00ed \u0111\u01b0\u1ee3c th\u1ea3 ban \u0111\u1ea7u l\u00e0 A. 0,30 s. B. 0,68 s. C. 0,26 s. D. 0,28 s. TRANG 115","CH\u01af\u01a0NG 7: H\u1ea0T NH\u00c2N NGUY\u00caN T\u1eec \u2013 CH\u1ee6 \u0110\u1ec0 4 \uf034 V\u00ed D\u1ee5 3: (\u0110H-2017) M\u1ed9t l\u00f2 xo nh\u1eb9 c\u00f3 \u0111\u1ed9 c\u1ee9ng 75N\/m, \u0111\u1ea7u tr\u00ean c\u1ee7a l\u00f2 xo treo v\u00e0o m\u1ed9t \u0111i\u1ec3m c\u1ed1 \u0111\u1ecbnh. V\u1eadt A c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng 0,1kg \u0111\u01b0\u1ee3c treo v\u00e0o \u0111\u1ea7u d\u01b0\u1edbi c\u1ee7a l\u00f2 xo. V\u1eadt B c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng 0,2kg treo v\u00e0o v\u1eadt A b\u1eb1ng m\u1ed9t s\u1ee3i d\u00e2y m\u1ec1m, nh\u1eb9 kh\u00f4ng d\u00e3n v\u00e0 \u0111\u1ee7 d\u00e0i \u0111\u1ec3 khi chuy\u1ec3n \u0111\u1ed9ng v\u1eadt A v\u00e0 v\u1eadt B kh\u00f4ng va ch\u1ea1m v\u00e0o nhau nh\u01b0 h\u00ecnh b\u00ean. Ban \u0111\u1ea7u gi\u1eef cho v\u1eadt B \u0111\u1ec3 l\u00f2 xo c\u00f3 tr\u1ee5c th\u1eb3ng \u0111\u1ee9ng v\u00e0 d\u00e3n 9,66cm ( coi 9,66 = 4 + 4 2 ) r\u1ed3i th\u1ea3 nh\u1eb9. L\u1ea5y g=10m\/s2 v\u00e0 \u03c02=10. Th\u1eddi gian t\u00ednh t\u1eeb l\u00fac th\u1ea3 v\u1eadt B \u0111\u1ebfn khi v\u1eadt A d\u1eebng l\u1ea1i l\u1ea7n \u0111\u1ea7u ti\u00ean l\u00e0: A. 0,19s B. 0,21s C. 0,17s D. 0,23s TRANG 116","CH\u01af\u01a0NG 7: H\u1ea0T NH\u00c2N NGUY\u00caN T\u1eec \u2013 CH\u1ee6 \u0110\u1ec0 4 CHUY\u00caN \u0110\u1ec0 N\u00c2NG CAO BI\u1ebeN C\u1ed0 L\u00c0M THAY \u0110\u1ed4I VTCB C\u1ee6A V\u1eacT PH\u1ea6N 4: BI\u1ebeN C\u1ed0 L\u00c0M THAY \u0110\u1ed4I V\u1eca TR\u00cd C\u00c2N B\u1eb0NG C\u1ee6A V\u1eacT TRANG 117","CH\u01af\u01a0NG 7: H\u1ea0T NH\u00c2N NGUY\u00caN T\u1eec \u2013 CH\u1ee6 \u0110\u1ec0 4 \uf032 V\u00ed d\u1ee5 1 (\u0110H-2013): M\u1ed9t con l\u1eafc l\u00f2 xo g\u1ed3m v\u1eadt nh\u1ecf c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng 100g v\u00e0 l\u00f2 xo nh\u1eb9 c\u00f3 \u0111\u1ed9 c\u1ee9ng 40N\/m \u0111\u01b0\u1ee3c \u0111\u1eb7t tr\u00ean m\u1eb7t ph\u1eb3ng n\u1eb1m ngang kh\u00f4ng ma s\u00e1t. V\u1eadt nh\u1ecf \u0111ang n\u1eb1m y\u00ean \u1edf v\u1ecb tr\u00ed c\u00e2n b\u1eb1ng, t\u1ea1i t=0 t\u00e1c d\u1ee5ng m\u1ed9t l\u1ef1c F=2N l\u00ean v\u1eadt nh\u1ecf nh\u01b0 h\u00ecnh v\u1ebd cho con l\u1eafc dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a \u0111\u1ebfn th\u1eddi \u0111i\u1ec3m t = \uf070 s th\u00ec ng\u1eebng t\u00e1c d\u1ee5ng l\u1ef1c F. Dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a c\u1ee7a con l\u1eafc sau khi kh\u00f4ng c\u00f2n l\u1ef1c F t\u00e1c d\u1ee5ng c\u00f3 3 bi\u00ean \u0111\u1ed9 b\u1eb1ng bao nhi\u00eau \uf032 V\u00ed d\u1ee5 2: Con l\u1eafc l\u00f2 xo g\u1ed3m l\u00f2 xo c\u00f3 \u0111\u1ed9 c\u1ee9ng K=10 N\/m; v\u1eadt n\u1eb7ng c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng m v\u00e0 mang \u0111i\u1ec7n t\u00edch q=5.10-5C. Ban \u0111\u1ea7u v\u1eadt dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a v\u1edbi bi\u00ean \u0111\u1ed9 5cm theo ph\u01b0\u01a1ng ngang. Khi v\u1eadt \u0111i qua v\u1ecb tr\u00ed c\u00e2n b\u1eb1ng, ng\u01b0\u1eddi ta thi\u1ebft l\u1eadp m\u1ed9t \u0111i\u1ec7n tr\u01b0\u1eddng \u0111\u1ec1u n\u1eb1m ngang c\u00f3 c\u01b0\u1eddng \u0111\u1ed9 E=104 V\/m. Bi\u00ean \u0111\u1ed9 dao \u0111\u1ed9ng c\u1ee7a v\u1eadt khi c\u00f3 \u0111i\u1ec7n tr\u01b0\u1eddng l\u00e0 TRANG 118","CH\u01af\u01a0NG 7: H\u1ea0T NH\u00c2N NGUY\u00caN T\u1eec \u2013 CH\u1ee6 \u0110\u1ec0 4 \uf032 V\u00ed d\u1ee5 3: M\u1ed9t con l\u1eafc l\u00f2 xo g\u1ed3m l\u00f2 xo c\u00f3 \u0111\u1ed9 c\u1ee9ng 100N\/m v\u00e0 v\u1eadt n\u1eb7ng c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng 250g mang \u0111i\u1ec7n t\u00edch 100 \u03bcC. Ban \u0111\u1ea7u v\u1eadt dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a v\u1edbi bi\u00ean \u0111\u1ed9 3cm theo ph\u01b0\u01a1ng th\u1eb3ng \u0111\u1ee9ng. Khi v\u1eadt \u0111i qua v\u1ecb tr\u00ed l\u00f2 xo d\u00e3n 1,5cm ng\u01b0\u1eddi ta b\u1eaft \u0111\u1ea7u thi\u1ebft l\u1eadp m\u1ed9t \u0111i\u1ec7n tr\u01b0\u1eddng \u0111\u1ec1u c\u00f3 ph\u01b0\u01a1ng th\u1eb3ng \u0111\u1ee9ng v\u00e0 h\u01b0\u1edbng l\u00ean c\u00f3 c\u01b0\u1eddng \u0111\u1ed9 E=5.104V\/m. L\u1ea5y g=10m\/s2. T\u00ednh bi\u00ean \u0111\u1ed9 dao \u0111\u1ed9ng c\u1ee7a v\u1eadt sau khi c\u00f3 \u0111i\u1ec7n tr\u01b0\u1eddng? TRANG 119","CH\u01af\u01a0NG 7: H\u1ea0T NH\u00c2N NGUY\u00caN T\u1eec \u2013 CH\u1ee6 \u0110\u1ec0 4 \u2756 B\u00c0I T\u1eacP T\u1ef0 LUY\u1ec6N C\u00e2u 1: Con l\u1eafc l\u00f2 xo c\u00f3 \u0111\u1ed9 c\u1ee9ng k=100N\/m v\u00e0 qu\u1ea3 c\u1ea7u mang \u0111i\u1ec7n t\u00edch q=100\u03bcC c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng m=1kg \u0111ang dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a theo ph\u01b0\u01a1ng ngang kh\u00f4ng ma s\u00e1t. Khi \u0111i qua v\u1ecb tr\u00ed c\u00e2n b\u1eb1ng v\u1edbi t\u1ed1c \u0111\u1ed9 40 3 cm\/s th\u00ec xu\u1ea5t hi\u1ec7n \u0111i\u1ec7n tr\u01b0\u1eddng \u0111\u1ec1u c\u00f3 ph\u01b0\u01a1ng ngang d\u1ecdc tr\u1ee5c l\u00f2 xo v\u1edbi c\u01b0\u1eddng \u0111\u1ed9 E=2.104 V\/m. C\u01a1 n\u0103ng c\u1ee7a con l\u1eafc sau khi c\u00f3 \u0111i\u1ec7n tr\u01b0\u1eddng l\u00e0: A. 0,032J B. 0,32J C. 32J D. 3,2J C\u00e2u 2: M\u1ed9t con l\u1eafc l\u00f2 xo g\u1ed3m qu\u1ea3 c\u1ea7u nh\u1ecf c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng 200g mang \u0111i\u1ec7n t\u00edch 5\u03bcC v\u00e0 l\u00f2 xo c\u00f3 \u0111\u1ed9 c\u1ee9ng 50N\/m c\u00f3 th\u1ec3 dao \u0111\u1ed9ng tr\u00ean m\u1eb7t ph\u1eb3ng n\u1eb1m ngang kh\u00f4ng ma s\u00e1t. Th\u1eddi \u0111i\u1ec3m ban \u0111\u1ea7u, ng\u01b0\u1eddi ta k\u00e9o v\u1eadt t\u1edbi v\u1ecb tr\u00ed l\u00f2 xo d\u00e3n 4cm r\u1ed3i th\u1ea3 nh\u1eb9. \u0110\u1ebfn th\u1eddi \u0111i\u1ec3m t=0,2s, thi\u1ebft l\u1eadp \u0111i\u1ec7n tr\u01b0\u1eddng kh\u00f4ng \u0111\u1ed5i trong th\u1eddi gian 0,2s, bi\u1ebft \u0111i\u1ec7n tr\u01b0\u1eddng \u0111\u1ec1u n\u1eb1m ngang d\u1ecdc theo tr\u1ee5c c\u1ee7a l\u00f2 xo h\u01b0\u1edbng ra xa \u0111\u1ea7u treo l\u00f2 xo v\u00e0 c\u00f3 c\u01b0\u1eddng \u0111\u1ed9 l\u00e0 105V\/m. L\u1ea5y g=10=\u03c02 m\/s2. T\u00ednh t\u1ed1c \u0111\u1ed9 c\u1ef1c \u0111\u1ea1i qu\u1ea3 c\u1ea7u \u0111\u1ea1t \u0111\u01b0\u1ee3c sau \u0111\u00f3 A. 35\u03c0 cm\/s B. 30\u03c0 cm\/s C. 25\u03c0 cm\/s D. 20\u03c0 cm\/s C\u00e2u 3: Con l\u1eafc g\u1ed3m l\u00f2 xo c\u00f3 \u0111\u1ed9 c\u1ee9ng K=100N\/m ; v\u1eadt n\u1eb7ng c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng 200 g v\u00e0 \u0111i\u1ec7n t\u00edch q = \u2212100\uf06dC Ban \u0111\u1ea7u v\u1eadt dao \u0111\u1ed9ng \u0111i\u1ec1u h\u00f2a v\u1edbi bi\u00ean \u0111\u1ed9 5cm theo ph\u01b0\u01a1ng th\u1eb3ng \u0111\u1ee9ng. Khi v\u1eadt \u0111i qua v\u1ecb tr\u00ed c\u00e2n b\u1eb1ng ng\u01b0\u1eddi ta thi\u1ebft l\u1eadp m\u1ed9t \u0111i\u1ec7n tr\u01b0\u1eddng \u0111\u1ec1u th\u1eb3ng \u0111\u1ee9ng, h\u01b0\u1edbng l\u00ean c\u00f3 c\u01b0\u1eddng \u0111\u1ed9 E=0,12 MV\/m. Bi\u00ean \u0111\u1ed9 dao \u0111\u1ed9ng c\u1ee7a v\u1eadt khi c\u00f3 \u0111i\u1ec7n tr\u01b0\u1eddng l\u00e0 TRANG 120",""]