Bếp điện loại 220V-1000W đun ấm nước chứa 2 lít nước có nhiệt độ ban đầu là 200C. Hiệu suất của quá trình đun sôi là 86%.
a. Sau bao lâu nước sôi? Biết rằng hiệu điện thế làm việc bằng 220V. Nhiệt dung riêng của nước là 4200J/Kg.K
b. Nếu chập đôi dây nối trên thì công suất của bếp bằng bao nhiêu?
Cường độ dòng điện qua bấp bằng bao nhiêu?
Nếu dùng bếp đun nước như lượng nước ở trên thì sau bao lâu nước sôi?
Some of the comparisons in these sentences are incorrect. Underline and correct the mistakes.
1. Of the three types of cattle in the Mongolian desert,the sleep is slower.
→ Of the three types of cattle in the Mongolian desert, the sleep is slower.
2. A City has most of interesting activities than the countryside.
→ A City has most of the interesting activities than in the countryside.
3. They City offers more services.It's much convenienter than thecountryside.
→ The City offers more services. It's much convenient than in the countryside.
4. My village has only 1,200 people.It's not so crowded than the City.
→ My village has only 1,200 people. It's not so crowding the same as the City.
1. Tom loves (A) flying(B) his handmade kites. They looks (C) great up in (D) the sky.
- Looks → Look
2. He goes (A) to school in the morning and (B) he helps (C) his family herding (D) buffaloes.
- and → after
3. The famers have (A) to word early (B) in the morning than (C) the collar workers do (D).
- famers → farmers
- than → then
4. Living in the city offers (A) more opportunities for well (B) promotion, higer (C) eduction and better (D) facilities.
- higer → higher
5. It takes less (A) money to live in the countryside because our cattle and plants provide (B) us to (C) the most (D) of our needs.
- to → with
- the most → most
6. They live in (A) exactly (B) the same (C) way to (D) other people.
- Bạn nên bỏ từ "exactly" luôn vì nó trở nên dư thừa trong câu, nó cùng nghĩa với từ "the same".
7. I remember (A) these days in the past. We had (B) to work harder (C) but very satisfied (D).
- harder → hard