user-avatar
thanhsonbato2019
2 năm trước
Từ độ cao 4m( so với mặt đất) ng ta ném một vật có m=0,2kg xuống dưới theo phương thẳng đứng với vận tốc ban đầ là 2m/s lấy g=10m/s2 chọn mốc thế năng tại mặt đất. A) tính cơ năng của vật tại vị trí ném B) tính vật tốc của vật khi cách mặt đất 2m C) tính độ cao cực đại mà vật đạt được D) ở độ cao nào thì thế năng bằng một nửa động năng
Thích Trả lời Chia sẻ

Các câu hỏi liên quan

Bài 1. Chọn đáp án đúng (A, B, C hoặc D) để điền vào chỗ trống 1.They_________the bus yesterday. A. don’t catch B. weren’t catch C. didn’t catch D. not catch 2. My sister_________home last night. A. comes B. come C. came D. was come 3. My father_________tired when I _________ home. A. was – got B. is – get C. was – getted D. were – got 4. What_________you_________two days ago? A. do – do B. did – did C. do – did D. did – do 5.Where_________your family_________on the summer holiday last year? A. do – go B. does – go C.did – go D. did – went 6. We_________David in town a few days ago. A. did see B. was saw C. did saw D. saw 7. It was cold, so I_________ the window. A. shut B.was shut C. am shut D.shutted 8. I_________to the cinema three times last week. A.was go B. went C. did go D.goed 9.What_________you_________last weekend? A.were/do B.did/did C.did/do D.do/did 10.The police_________on my way home last night. A. was stop B.stopped C.stops D.stopping 11. The film wasn’t very good. I_________ it very much. A.ẹnjoyed B.wasn’t enjoy C.didn’t ẹnjoyed D. didn’t enjoy 12.The bed was very uncomfortable. I_________sleep very well. A.didn’t B.did C.wasn’t D.not 13. The window was opened and a bird_________into the room. A.fly B. flew C. was flew D.did fly 14. I_________a lot of money yesterday. I_________an expensive dress. A.spend/buy B.spent/buy C.spent/bought D.was spent/bought. 15.My friend (give) __________ me a bar of chocolate yesterday but I (leave) __________ it at school. A. give – leave             B. gave– left             C. give– left                 D. gives – leaves 16.Your friend (be) __________ at your house last weekend. A. is                  B. are                C. was                 D. were 17.They (not be) __________excited about the film last night. A. wasn’t                  B. isn’t               C. aren’t                 D. weren’t 18.My children (not do) __________ their homework last night . A. didn’t do                  B. didn’t – did                C. don’t – did                 D. did – do 19.You (live) __________here five years ago? A.does- lives                   B. do-live                C. did-live                D. lived 20.They (watch) __________TV late at night yesterday. A. watches                  B. watching                C. watch                 D. watched Làm hết giúp mình nhé ! Mình đang cần gấp !

2018 © Loga - Không Ngừng Sáng Tạo - Bùng Cháy Đam Mê
Loga Team