... cos(10t ) (cm) E0 n =- n n t A B 15 C A 10cm B 100cm 27 D (m/s2 C cm D 20cm 1 A 1h = t1 B 3h C 2h = 1,5 N1 D 4h trung A 24 B 12 C 25 D 11 A B C Lam D Cam B 1cm C -1 m D - cm 0,8 m/s A A cm ... 13,6 13 A Hz 12 B Hz 14 C Hz 15 D A 0,75mm B 0,25mm C 2mm D 1,5mm = 0,1 (rad) Kh A B C Hz - 0,02(rad) - 0,05(rad) D A B C D , L, C = 50 = 200 A 125 ( rad/s) B 100 ( rad/s) C 150 ( rad/s) D 175 ... 59: 250 cos 100 t C 200 W B 300 W A 300W 60: = 0,8 A 1,5A D 200W B 0,25 A C 0,75 A - D 0,5 A -Trang 6/6 ...