Khi nói về chuyển động tròn đều của một vật, nhận xét nào sau đây là sai?
Tốc độ góc của vật luôn không đổi.
Vận tốc của vật luôn tiếp tuyến với quỹ đạo.
Chu kì quay càng nhỏ thì vật chuyển động càng nhanh.
Gia tốc của vật cùng chiều với vận tốc của vật.
Hãy suy nghĩ và trả lời câu hỏi trước khi xem đáp án
Khi nói về chuyển động tròn đều của một vật:
- Tốc độ góc của vật luôn không đổi.
- Vận tốc của vật luôn tiếp tuyến với quỹ đạo.
- Chu kì quay càng nhỏ thì vật chuyển động càng nhanh.
Đáp án D
Tài liệu "Bộ Đề Kiểm Tra Học Kì II - Năm Học 2023-2024 - Vật Lí 10" tổng hợp các đề kiểm tra từ các trường THPT trên toàn quốc, được biên soạn bám sát chương trình học. Các đề thi gồm các dạng bài trắc nghiệm và tự luận, tập trung vào các chủ đề trọng tâm: động lực học chất điểm, cân bằng và chuyển động của vật rắn, cơ năng, và các định luật bảo toàn. Tài liệu giúp học sinh ôn tập hiệu quả, nắm vững kiến thức, rèn luyện kỹ năng giải bài tập và chuẩn bị tốt cho kỳ thi học kỳ II.
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