Thả một miếng sắt được nung nóng tới 70°C vào một bình đựng 500g nước ở nhiệt độ 20°C làm cho nước nóng đến 24°C. Cho rằng chỉ xảy ra sự trao đổi nhiệt giữa miếng sắt và nước, hãy tính nhiệt độ của miếng sắt ngay khi có cân bằng nhiệt ? Biết nhiệt dung riêng của sắt là 460J/kg.K và nhiệt dung riêng của nước là 4200J/kg.K. * 70 °C 24 °C 20 °C 46 °C

Các câu hỏi liên quan

Nhanh nhé higpfpwkdb pwdvkpbqexpj1gedobr1ohdv1p4i d9ehxh9egdi01g3sih13oudvw9jzv9ejzgjeczi1wbjvwKPv2zonvkpc 1hebxkpwvshp1ecx0jx1ywdv1e djo1ebx1vezb1roj 9hs dpkb1rxj0v1ekfbi0rbfj01vefi0b1rkcbq0je divefi0v1ek0xb1k0rvl01 rj9c 1rk0 j01ebxhov1eoxv1joebxn1 ẹp edhovwoj dk0nefu9 edk01ehodv1joe dj91 eh9fvo1he dpj,wpjx fuedcjpcri0wdb1j0ec1pjevdj0evdjpwvsjpwv2jp1🤔😏😝🤧😌🤔🤤🤮🤪😌😮🤐😌🥴☹😯🧐☹😌😮🥶🙁🥸🥶😯🤥☹🥴😢🤨🧐🥴😯😟🧐😥🤯🤓😰😟😯😣🥺😎😨😰😦🧐🧐😰🤥😮🤯🥶🤥😮🤠🥶😮😷🤠🥶🤥😮🥵🤠🙄😮🤠🥶🤥🤐😮😌🥶😮🤠🥶🤐😌🥸🤠🥶😜😌😮🤠🥶🤐😮😌😌🤐😮🥶🙁🙁🤐🤥🥶😷😮🙁🤥🤐🥶😮🤐😌🤠😮🥶😜😮😌🥳🥶😜😮🥵😷🤠😌😮😷😜😌🥵🤠🤨🥵😷😮🤤🤔🤨🤮🤯🤤🤔🤮🤨🤠🤤🤔🤮🤨😏🤯🤔😜🤮🤨🤯😏🤫🤮🤨😶🤯🤫🤮😶🤫🤨🤮😏🤫🤧🤕🤨🙄🤢🥸😘🙄😴😝😔🥸😗😴😑🤮😜😴🥸😐🤧🤢🤔😏😜😐🤧🤠😜😐🤮🤪😑🤧🤪😶🥸🤪😑🤮🤪😑🤮😜😐😔😘🤑🤮😜😐😔😝😔😘😝😔😘😝😔4😄😚4t😁😊😆😙😙😉😙😏😉🥲🤗😉😇🤭😉😇🤭😉😇🤭😉😇🤭😄😇🤭😄😇🤗😄😇🤗😄😇🤭😃😇🤗😄😇🤗😃😊🤗😃😇🤗😃😇🤗😃😇🤗😄😇🤗😄😇🥰😄🤭😄😙😏😄😇

e cần trc 9h30 ạ 31. Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions . Every day on radio, on TV, and in the newspaper, we hear, see or read about many problems in the world, for example, pollution problems. Air pollution is the first kind. It mostly comes from fumes released from motorbikes, cars, airplanes, trains and poisonous gases emitted from factories. Also, waste is dumped anywhere, even in the city where many people are living. The second pollution problem is sea pollution. Many people earn their living from fishing in the sea. But the sea has become so polluted from oil spills and factory wastes that the fish are dying. This is not only killing the fish, but is also affecting those people who eat fish. Seldom do you find a place nowadays that is not polluted. This problem is growing more difficult everyday. We must find a good solution that makes the world a better place to live. Question 28. We hear, see and read about problems in the world _________ (1 Điểm) A. every day B. once a week C. every week D. every year 32. Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions . Every day on radio, on TV, and in the newspaper, we hear, see or read about many problems in the world, for example, pollution problems. Air pollution is the first kind. It mostly comes from fumes released from motorbikes, cars, airplanes, trains and poisonous gases emitted from factories. Also, waste is dumped anywhere, even in the city where many people are living. The second pollution problem is sea pollution. Many people earn their living from fishing in the sea. But the sea has become so polluted from oil spills and factory wastes that the fish are dying. This is not only killing the fish, but is also affecting those people who eat fish. Seldom do you find a place nowadays that is not polluted. This problem is growing more difficult everyday. We must find a good solution that makes the world a better place to live. Question 29. What causes the air pollution? (1 Điểm) A. factory wastes B. many people earn their living from fishing in the sea. C. oils spills D. fumes from vehicles and poisonous gases from factories 33. Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions . Every day on radio, on TV, and in the newspaper, we hear, see or read about many problems in the world, for example, pollution problems. Air pollution is the first kind. It mostly comes from fumes released from motorbikes, cars, airplanes, trains and poisonous gases emitted from factories. Also, waste is dumped anywhere, even in the city where many people are living. The second pollution problem is sea pollution. Many people earn their living from fishing in the sea. But the sea has become so polluted from oil spills and factory wastes that the fish are dying. This is not only killing the fish, but is also affecting those people who eat fish. Seldom do you find a place nowadays that is not polluted. This problem is growing more difficult everyday. We must find a good solution that makes the world a better place to live. Question 30. The sea has become polluted because of_________ . (1 Điểm) A. oil spills B. factory wastes C. smoke from factories D. oil spills and factories wastes 34. Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions . Every day on radio, on TV, and in the newspaper, we hear, see or read about many problems in the world, for example, pollution problems. Air pollution is the first kind. It mostly comes from fumes released from motorbikes, cars, airplanes, trains and poisonous gases emitted from factories. Also, waste is dumped anywhere, even in the city where many people are living. The second pollution problem is sea pollution. Many people earn their living from fishing in the sea. But the sea has become so polluted from oil spills and factory wastes that the fish are dying. This is not only killing the fish, but is also affecting those people who eat fish. Seldom do you find a place nowadays that is not polluted. This problem is growing more difficult everyday. We must find a good solution that makes the world a better place to live. Question 31. In order to make the world a better place to live, we _________ . (1 Điểm) A. should not prevent pollution B. must find a good solution. C. should kill the fish. D. must find a place that is not pollu