Cho chất điểm khối lượng 50g dao động điều hòa được mô tả bởi phương trình x = 10sin(4πt + π/2) (cm.s). a. Viết phương trình vận tốc, gia tốc của chất điểm. b. Giá trị cực đại của vận tốc, gia tốc. c. Vận tốc của vật lúc đi qua vịtrí có li độ5cm. d. Vận tốc của chất điểm vào thời điểm t = 2s e. Xác định vịtrí mà ởđó vận tốc đạt ½ giá trị cực đại. f. Gia tốc của vật lúc nó ở biên và lúc vật có vận tốc 6,28(cm/s) g. Xác định động năng, thếnăng, cơ năng khi vật có tọa độbằng một nửa biên độ. giúp em vs ạ tối phải hộp bài r . Giải câu E F G giùm em ạ

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