Phương trình của một chất điểm có dạng

Phương trình chuyển động của một chất điểm có dạng: x=5+60t  (x tính bằng km, t tính bằng h). Vị trí ban đầu và vận tốc của chất điểm là

A.Tại gốc tọa độ O, với vận tốc 5 km/h.

B.Tại gốc tọa độ O, với vận tốc 60 km/h.

C.Từ điểm M cách O là 5 km, với vận tốc 5 km/h.

D.Từ điểm M cách O là 5 km, với vận tốc 60 km/h.

Đáp án và lời giải

Đáp án:D

Lời giải:Lời giải:
Phương trình chuyển động của chuyển động thẳng đều: x=x0+v. t .
Theo bài: x=5+60t 
⇒x0=5 kmv=60 km/h ⇒ Chọn D

Vậy đáp án đúng là D.

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  Question: The word “harness" in paragraph 4 is closest in meaning to