Đáp án:
\(2,{4.10^{ - 17}}N\)
Giải thích các bước giải:
Lực Lorenxo tác dụng lên electron
\[\begin{array}{l}f = \left| q \right|vB\sin \alpha = 1,{6.10^{ - 19}}{.5.10^6}{.3.10^{ - 5}}.\sin {90^0}\\ = 2,{4.10^{ - 17}}N\end{array}\]
một xí nghiệp dệt thảm được giao làm một sô thảm xuất khẩu trong 20 ngày xí nghiệp đã tăng năng suất lên 20%nên sau 18 ngày không những đã làm xong số tham được giao mà còn làm thêm được 24 chiếc nữa tính số thảm mà xí nghiệp đã làm trong 18 ngày
Một thửa ruộng hình chữ nhật có chiều dài 25 m chiều rộng 15 m khi vẽ trên bản đồ với tỉ lệ 1: 500 thì diện tích hình vẽ thửa ruộng là bao nhiêu ? Help mình với!!!
Ai giúp mình câu này vs ạ, e cần hơi gấp nên cảm ơn mn rất nhiều!!!
Giúp e vs ạ 🥺☹️🥲😔 giúp nhanh vs
"Xưa nhà Thương đến vua Bàn Canh năm lần dời đô; nhà Chu đến vua Thành Vương cũng ba lần dời đô. Phải đâu các vua thời Tam Đại theo ý riêng mình mà tự tiện chuyên dời? Chỉ vì muốn đóng đô ở trung tâm, mini toan nghiệp lớn, tính kế muôn đời cho con cháu; trên vâng mệnh trời, dưới theo ý dân, nếu thấy thuận tiện thì thay đổi. Cho nên vân mrớc lâu dài, phong tục phồn thịnh. Thế mà hai nhà Đinh, Lê lại theo ý riêng mình, khinh thường mệnh trời, không nói theo dấu cũ của Thượng, Chu, cứ đóng ven đô thành ở nơi đây, khiến cho triều đại không được bền lâu, số vận ngắn ngủi, trăm họ phải hao tốn, muôn vật không được thích nghi. Trẫm rất đau xót về việc đó, không thể không dời đổi." . * * * * - câu hỏi : Dựa vào văn bản chứa đoạn văn trên, hãy viết một đoạn văn khoảng 10 - 12 câu theo cách lập luận diễn dịch để làm rõ sự kết hợp hài hòa giữa lí và tình trong lập luận của tác giả, trong đoạn có sử dụng một câu ghép và một thán từ (gạch chân và chủ thích rõ),
IV. Choose the correct answer A, B, C or D to fill each blank in the following passage. I have a very interesting and (1) hobby. I make short video clips with my digital camera. It was my birthday present from my parents last year. Since then, I have (2) three short films. It’s great fun! I started asking my friends and relatives to take (3) in the films. I have tried to write the story for my video clips. When I have finished the script, 1 make copies for the “actors”. Each scene is small and they can look at the words just (4) we start filming. We film at the weekend in my neighbourhood, (5) no one has to travel far. When the video clip is finished, I invite all the “actors” and we watch the film at my house. 1. A. enjoy B. enjoyed C. enjoying D. enjoyable 2. A. done B. played C. made D. watched 3. A. part B. role C. scene D. film 4. A. before B. after C. only D. until 5. A. although B. because C. but D. so V. Read the passage, and then choose the correct answer. (For 7A) Stamp collecting is an interesting hobby. You can learn many things, such as the geography of a country from stamps. Postal stamps are a source of interesting facts and important dates about every country in the world. It makes stamp collecting become very popular. As you look at the pages of a stamp album, you can learn interesting details of foreign customs, arts, literature, history and culture. Their colours can make you feel relaxed and happy. Collecting stamps can become a business. If you are lucky in finding a special stamp, it will bring you some money besides knowledge and pleasure. 1. Stamp collecting is an interesting hobby because . A. you can learn many things such as the geography of a country from stamps B. stamps give you interesting facts and important dates about a country C. it is very important to collect stamps D. A and B are correct 2. All of the following are true EXCEPT . A. stamps can make you relaxed and happy B. stamps can make you know more C. stamp collecting can make you famous D. you can earn money from your collection if you are lucky 3. According to the passage, it is true to say that . A. stamp collecting helps you become rich and famous B. stamp collecting is a very popular hobby C. stamp collectors can earn a lot of money from stamp collecting D. stamp collecting is a hobby that costs you a lot of money 4. The word “business” in the last paragraph is closest in meaning to . A. the activity of collecting stamps B. the activity of selling stamps from other countries C. the activity of buying stamps from other countries D. the activity of buying or selling something 5. The main idea of the passage is . A. the history of stamp collecting B. good things from stamp collecting C. the ways of stamp collecting D. famous stamp collectors VI. Make correct sentences from the words and phrases given. 1. When/ you/ start/ hobby? 2. We/ find/ make/ models/ very interesting/ because/ we/ should/ creative. 3. I/ think/ future/ people/ take up/ more/ outdoor activities. 4. My best friend/ not/ like/ mountain climbing/ because/ he/ afraid/ heights. 5. My sister/ enjoy/ cook/ and/ make/ new dishes/ her own.
Làm nhanh giúp mình với, cảm ơn các bạn nhìu!!
2. Read the text and choose the correct answer. If you enjoy cycling for pleasure, doing it in London can be a shock. There are not enough lanes especially for bikes, and making your way through the traffic can be very risky. But if you have great passion, cycling in London can be exciting, and it is an inexpensive way of keeping fit if you live there. Some cyclists don’t mind spending a lot of money on expensive bikes. However, if you just want a basic bike that is only for occasional use, there are many cheap choices. Several markets have cheap bikes on sale which may not be impressive to look at but should be satisfactory. You should buy a cycling helmet if you want to cycle in London. Wearing a cycling helmet is not compulsory in Britain, but it is a good idea to wear one for protection. 1. What is the main idea of the passage? A. Cycling helmets B. Cheap bicycles C. Bicycle markets D. Cycling in London 2. According to the passage, cycling in London is A. easy B. difficult C. tiring D. boring 3. The word “it” in line 3 refers to A. cycling B. passion C. excitement D. doing exercise 4. The difficulty of cycling in London is described in lines A. 2 B. 5 C. 5-6 D. 8-9 5. According to the passage, all the followings are true EXCEPT that A. It is compulsory to wear a helmet when cycling in Britain. B. Some bikes in London are cheap. C. There are not many lanes especially for bikes. D. Some cyclists don’t want to buy expensive bikes. 3. Make up sentences using the words and phrases given. 1. when/ I/ ten/ begin/ play football. 2. in/ future/ my father/ go abroad. 3. read/ books/ free time/ is/ favourite/ hobby. 4. I/ think/ skate/ more/ interesting/ mountain - climbing. 5. I /not/ know/ why/ my mother/ cook. 6. He/ collect/ books/ whenever/ have/ money. 7. How many/ paintings/ she/ paint? 8. I/ love/ flowers/ so/ I/ plant/ around/ house. PRACTICE TEST I. Find the word which has a different sound in the part underlined. 1. A. bird B. girl C. first D. sister 2. A. burn B. sun C. hurt D. turn 3. A. nurse B. picture C. surf D. return 4. A. neighbour B. favourite C. culture D. tourist 5. A. hobby B. hour C. hotel D. hot II. Choose the word which has a different stress pattern from the others. 6. A. reporter B. collector C. gardener D. newspaper 7. A. stamps B. album C. collector D. mountain 8. A. skating B. climbing C. gardening D. horse-riding 9. A. hate B. enjoy C. love D. like 10. A. unusual B. favourite C. popular D. common III. Choose the best answer A, B, C or D to complete the sentences. 11. There are many why it is important to have a hobby. A. answers B. reasons C. details D. facts 12. Will you making models in the future? A. pick up B. look for C. take up D. find 13. Do you think that hobby is and boring? A. easy B. difficult C. danger D. interesting 14. I love my sister’s paintings because she is very in using colours. A. careless B. care C. creative D. imagine 15. A hobby helps you to connect with people. A. other B. others C. another D. the other 16. I join a photography club, and all the members love a lot of beautiful photos. A. take B. taking C. make D. making 17. What does your father do his free time? A. in B. at C. on D. while 18.I think a hobby will always give you and help you . A. pleased - relax B. pleasure - relaxed C. pleased - relaxing D. pleasure - relax 19. You can share your stamps other collectors a stamp club. A. with - at B. to - at C. with - in D. to - in 20.I think this hobby does not cost you much, and you need is time. A. most B. all C. some D. all of 21. Nowadays people hours sitting in front of computers. A. take B. last C. set D. spend 22. I think you should take up swimming it is suitable for your health condition. A. so B. because C. although D. but 23. My family enjoys because we can sell vegetables and flowers money. A. garden - to B. gardening - for C. gardening - with D. garden - of 24. If your hobby is greeting card making, you can give your to your friends as presents. A. hobby B. money C. greetings D. products 25. My sister’s hobby is sewing, and she can get the sewing patterns from the magazines. A. fashion B. cooking C. sports D. science 26. My brother doesn’t like ice-skating because he thinks it is . A. danger B. in danger C. dangerous D. endangered 27. My sister is very keen on swimming, and she goes swimming three a week. A. time B. a time C. times D. timings 28. We often read the instructions carefully in order to make of the things we like best. A. meanings B. models C. copies D. uses 29. You need to be to follow eggshell carving because it may take two weeks to complete one shell. A. careful B. interested C. fit D. patient 30. If you choose sewing as your hobby, you will your own clothes. A. do B. make C. take D. get
Giúp mik nhé mai mik nộp r Rewrite these sentences with contractions.
Một chủ quán cà phê thống kê doanh thu như sau: - Tháng 2/2021, trung bình mỗi ngày bán 30 ly cà phê đen và 25 ly cà phê sữa nên thu được 17640000 đồng - Tháng 3/2021, trung bình mỗi ngày bán 35 ly cà phê đen và 20 ly cà phê sữa nên thu về được 19440000 đồng Tính giá tiền một ly cà phên đen và một ly cà phê sữa biết giá không đổi trong hai tháng; các ngày chủ nhật quán đều nghỉ bán (ngày 1/2/2021 và ngày 1/3/2021 là thứ Hai).
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