bài 1 - đại cương dao động điều hòa

www.tuhoc.edu.vn T [s] f [Hz] T x f t N Acos( t ) Trong đó: x– A– – ( t+ ) – – TOPPER Chú ý – A, htttp://tuhoc.edu.vn/blog dương T A f L www.tuhoc.edu.vn A cm; B –1 cm; C – cm; D cm; t – /4) A –3 cm; – /4 C cm; /4 B –3 cm; /4 D cm; /4 A cm B –6 cm C 12 cm D –12 cm A cm B cm C cm D cm A 2cm; 0,5s B 2cm; 2s C 4cm; 0,5s D 4cm; 2s A T = 3s B T = 2s C T = 0,5s D T = 1s htttp://tuhoc.edu.vn/blog www.tuhoc.edu.vn v x A sin( t cm/s; m/s ) o max =A BT: vmin = 7–9 a v x Acos( t ) x cm/s2 ; m/s2 o max =A BT: amin = C–E x2 A2 v2 2 A a v A BT: 2 elip x a A elip AB htttp://tuhoc.edu.vn/blog www.tuhoc.edu.vn A B A C – A D A 90o B 180o C 270o D A C B D x A 5cos(2 t A 25,12cm/s C 12,56cm/s B 25,12m/s D 12,65cm/s A 62,8cm/s C – 62,8 cm/s B 62,8cm/s D 31,4 m/s A -947,5cm/s2 B 947,5cm/s2 C -74,5cm/s2 D 74,5cm/s2 /3)cm B C D A 6cm B 12cm C 15cm x E 5cos(2 t D 9cm /2) cm = 10 A 25cm/s; 5m/s2 B cm/s; 250cm/s2 C cm/s; m/s2 D 10 cm/s; 2m/s2 htttp://tuhoc.edu.vn/blog www.tuhoc.edu.vn M M0 t x O P 0, x t+ ) x OP OMcos( t t+ ) Acos( t ) A htttp://tuhoc.edu.vn/blog www.tuhoc.edu.vn x x1 O B1: x2 -A cos A x Acos( t ) x2: x1 A ? A cos cos x1 A B2: ? 1 2 B3: T t VD: x2 = A/2 ? A T/6 B T/12 C T/4 B1: cos 30o A 1 D T/2 ; cos A A 2 B2: A O -A A x t B3: T T 12 B BT: FG htttp://tuhoc.edu.vn/blog www.tuhoc.edu.vn x O x1 âm ) A cos B1: x2 -A Acos( t A x trí x1: x1 ? v1 ? B2: dương B3: T t VD: A 1/3s B 1/8s C 1/6s D 1/4s B1: -8 O x2 90o t1 x1 v B2: x x1 2 B3: t B BT: H I htttp://tuhoc.edu.vn/blog www.tuhoc.edu.vn B1: trí x1: 4A 2A chưa O x1 -A x2 A x x1 ? v1 dÊu > | < x2: t B2: n.T x2 ? v dÊu > | < t( t T) S = S1 + S2 A B3: = n.4A VD: 2cos(2 /T – = 61T/24 là: A 9cm B 27cm C 18cm D 12cm B1: -2 x2 90o O x x1 = 7T/24: = 61T/24: x1 v1 x2 v2 B2: t S 61 24 T 24 2T S1 T S2 B3: – S1 có: S2 = A = 2cm + S2 = 18cm C htttp://tuhoc.edu.vn/blog BT: J-L www.tuhoc.edu.vn B1: 4A x1 O n.4A s0 t = t1 + t2 x2 -A 2A chưa S A x B2: 1 = n.T A VD: t– là: A 41/6(s) B 27/4(s) C 20/3(s) D 13/2(s) B1: -5 150o O 2,5 x S = 67,5cm =3.4.5 + 7,5 t= t1 + t2 B2: – t1 = 3.T = 6s – t2 1500 t 5T 12 (s) t 41 (s) A BT: ef htttp://tuhoc.edu.vn/blog www.tuhoc.edu.vn t B1: x1 O -A x0 x2 A x n.T t B2: n.T 2.n VD: t - /3)cm A B C D B1: -3 O 1,5 t2 t T x t1 T 2,5 t 2T 0,5T B2: B BT: M-Q htttp://tuhoc.edu.vn/blog 10 www.tuhoc.edu.vn x1 x0 O x0 -A x2 A x n = 2k x0 n = 2k x VD: A 12061 s 24 B 12049 s 24 C 4cos(4 t 12025 s 24 /6)cm D Đáp án khác B1: o 30 -4 O x 1005 B2: = 2cm 1005T ): t t BT: 1005T T 12 A T 12 12061 s 24 R-T htttp://tuhoc.edu.vn/blog 11 www.tuhoc.edu.vn B1: x1 O x2 -A A x B2: B3: t o VD: t – /4)cm A x = 5cm B x = 6cm C x = –5cm D x = –6cm B1: -10 -6 O 10 x B2: 0,5.2 rad B BT: U-X htttp://tuhoc.edu.vn/blog 12 www.tuhoc.edu.vn x t v tb x2 x1 t2 t1 |x2 – x1 không (0) v S t2 t1 VD: A 9A 2T B 9A 4T C A 2T D 5A 2T S -A -A/2 O A x t T v A BT: 3A S t 3A T 9A 2T YZ htttp://tuhoc.edu.vn/blog 13 www.tuhoc.edu.vn t > T/2, t' < T/2 t < T/2 Tách: t Smax 2Asin Smin 2A(1 cos 2 ) n.T/2 t Smax n.2A 2A sin Smin n.2A 2A.(1 cos 2 ) VD: max A 1,5A B 2A C A t -A -A/2 O D 3A 2T T A x S2 2Acos( ) BT: T = 2A A + S2 = 3A D a-d htttp://tuhoc.edu.vn/blog 14 www.tuhoc.edu.vn F B T/4 = A 2 C T/6 D T/8 A 2T/3 B T/4 A C T/6 D 5T/12 A 5T/4 B T/4 C 2T/3 D 3T/4 A 5T/12 B 5T/4 C 2T/3 D 7T/12 A T/12 G H I J Qu πt + π/3) cm A S = 12 cm C S = 18 cm B S = 24 cm D S = cm K Qu πt + π/3) cm A S = 12 cm C S = 18 cm B S = 24 cm D S = cm L 5cos(8πt + π A S = 15 cm C S = 120 cm B S = 135 cm D S = 16 cm htttp://tuhoc.edu.vn/blog 15 www.tuhoc.edu.vn M 1=2,2 (s) t2 =0 A B C D N t - /2) cm A B C D O π/6) (x t (5πt + A B C D P t + /6) + (cm) A B C D Q 6) = 3sin(5 t + A B C D R πt – π/2) cm A C t = 61/6 (s) t = 25/6 (s) B D t = 9/5 (s) t = 37/6 (s) S A t = 4,5 (s) B t = 2,5 (s) C t = (s) D t = 0,5 (s) A t = 5/6(s) B t = 11/6(s) C t = 7/6(s) D 11/12 (s) T htttp://tuhoc.edu.vn/blog 16 www.tuhoc.edu.vn U = 4cos(2 t+ )cm A -2cm B 2cm C D - V = = 2cos(4 t + )cm A 2cm B - cm C - cm W D cm = 6cos(4 t- A 0cm/s B -12 cm/s C 12 D - 12 cm/s cm/s X A 3 C 0cm B 2 2 cm D Y A 9A/2T Z Trong (s) A v = 10 cm/s C v = 20 cm/s B 4A/T C 6A/T D 3A/T πt + π/4) cm B v = 15 cm/s D v = cm/s htttp://tuhoc.edu.vn/blog 17 www.tuhoc.edu.vn a A Smin = 10 m C Smin = 0,5 m B Smin = 2,5 m D Smin = m b πt + π/3) cm A Smax = 7,07 cm C Smax = 20 cm B Smax = 17,07 cm D Smax = 13,66 cm c Qu πt + π/3) cm t =1,5 s A Smin = 13,66 cm C Smin = 12,93 cm B Smin = 12,07 cm D Smin = 7,92 cm d πt – π/3) cm A Smax = 12 cm C Smax = 9,07 cm B Smax = 10,92 cm D Smax = 10,26 cm e t + )(cm) A 1/15 s B 2/15 s C 1/30 s f D 1/12 s t - /3)(dm) A 1/4 s B 1/2 s C 1/6 s D 1/12 s htttp://tuhoc.edu.vn/blog 18 www.tuhoc.edu.vn Câu Câu Câu D G D V B D H A W A A I D X C D A J K B A Y Z A A C L C a A B M A b B A N B c C B O D d A A A P A e B B A Q D f C C A R C g D A S B h E D T C i F D U A j htttp://tuhoc.edu.vn/blog 19 ... x VD: A 12 0 61 s 24 B 12 049 s 24 C 4cos(4 t 12 025 s 24 /6)cm D Đáp án khác B1: o 30 -4 O x 10 05 B2: = 2cm 10 05T ): t t BT: 10 05T T 12 A T 12 12 0 61 s 24 R-T htttp://tuhoc.edu.vn/blog 11 www.tuhoc.edu.vn... htttp://tuhoc.edu.vn/blog www.tuhoc.edu.vn x O x1 âm ) A cos B1: x2 -A Acos( t A x trí x1: x1 ? v1 ? B2: dương B3: T t VD: A 1/ 3s B 1/ 8s C 1/ 6s D 1/ 4s B1: -8 O x2 90o t1 x1 v B2: x x1 2 B3: t B BT: H I htttp://tuhoc.edu.vn/blog... x1 = 7T/24: = 61T/24: x1 v1 x2 v2 B2: t S 61 24 T 24 2T S1 T S2 B3: – S1 có: S2 = A = 2cm + S2 = 18 cm C htttp://tuhoc.edu.vn/blog BT: J-L www.tuhoc.edu.vn B1: 4A x1 O n.4A s0 t = t1 + t2 x2 -A