Vật dao động điều hòa theo phương trình x=Acos(ωt+φ) (cm) với A<0. Pha ban đầu của vật là
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Nội dung nào sau đây không phản ánh đúng mối liên hệ của Sử học với các ngành khoa học xã hội và nhân văn?
Bảng ghi thời gian rơi của một vật giữa hai điểm cố định
Thời gian rơi
Lần 1
Lần 2
Lần 3
Lần 4
0,345
0,346
0,342
0,343
Sai số tuyệt đối trung bình của thời gian rơi là bao nhiêu?
Hãy viết tập hợp \(A = \{ - 4; - 3; - 2; - 1;0;1;2;3;4\} \) bằng cách chỉ ra tính chất đặc trưng?
Loại virus đầu tiên từng được phát hiện là gì?
Những phát biểu nào sau đây đúng khi nói về vai trò của lớp vật liệu hấp thụ dao động trong đầu dò của máy siêu âm?
Cộng hòa Nam Phi tiếp giáp với đại dương nào sau đây?
Tính chính xác cao trong lĩnh vực cơ khí:
Hai quả bóng có khối lượng m1 = 6g, m2 = 12g được ép sát vào nhau trên mặt bàn nằm ngang. Khi buông tay, hai quả lăn được các quãng đường lần lượt là s1, s2 rồi dừng. Biết khi rời nhau, hai quả bóng chuyển động chậm dần cùng gia tốc. Tỉ số quãng đường của hai quả bóng chuyển động được là:
Tháng 12-1989, tại đảo Manta, Tổng thống Mỹ và Tổng bí thư Đảng Cộng sản Liên Xô đã cùng tuyên bố:
Một vật dao động điều hòa có phương trình . Li độ của vật tại thời điểm t = 0,25 (s) là:
Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the best answer to each of the following questions from 31 to 40.
In an era of increasing global awareness, debates around sustainable practices such as fair trade, organic farming, and recycling are gaining prominence. Farmers in developing countries are among the most vulnerable people, dependent on world commodity markets, middlemen, and unpredictable weather.
(I)Fair trade arrangements aim to support cooperative groups by guaranteeing prices above the world market rate and additional bonuses. (II) However, critics argue that fair trade may not lift a country out of poverty. (III)They claim that most of the money generated from sales goes to wealthy countries that promote these products. (IV)In fact, only about 5% of the sale price of a fair-trade chocolate bar (retailing for £1.73 in the UK) reaches the poor country.
Another significant trend is the rise of organic food, marketed as being free of chemicals, which appeals to consumers concerned about the dangers of chemicals in food. These chemicals are suspected of causing various health problems, including cancer and developmental issues in children. Despite these concerns, British farmers have not converted to organic farming in large enough numbers to meet the demand. As a result, supermarkets often import organic vegetables from distant countries, contributing to higher greenhouse gas emissions due to transportation. Environmentalists are now urging consumers to buy locally grown vegetables, even if they are pesticide-treated, suggesting a good wash can minimize the risk.
In recent years, a shift has occurred in how we handle waste. Once content to bury it in landfills or dump it at sea, we are now encouraged to recycle and treat waste as a resource. This shift has led to more widespread kerbside collections for various materials like paper, plastic, and metal. However, recycling has unintended consequences. Most of the UK's recyclables are sent to China or India, which incurs additional environmental costs from transportation. In these countries, workers often sort waste under dangerous conditions. Sometimes, materials that are sorted at home still end up in landfills because the market for them fluctuates.
While efforts to promote sustainability are commendable, they require constant evaluation to ensure they truly benefit people and the environment, rather than creating new inequalities or environmental harm.
Which of the following best summarizes the main point of the passage?
Ưu điểm của vaccine DNA tái tổ hợp là
Hậu quả của tình trạng thất nghiệp đối với các doanh nghiệp như thế nào?
Công nghiệp chế biến của Tây Nguyên đang được đẩy mạnh chủ yếu là nhờ
Cho thông tin sau:
Dù tương lai có thế nào đi chăng nữa, thì một điều chắc chắn là: EU sẽ tiếp tục coi thúc đẩy hòa bình và an ninh quốc tế, hợp tác phát triển, nhân quyền và ứng phó với khủng hoảng nhân đạo là trọng tâm của các chính sách đối ngoại và an ninh của mình.
(Nguồn: Đại sứ - Trưởng Phái đoàn EU Bruno Angelet)
Nhận định nào dưới đây là đúng/sai?
Choose A, B, C or D to answer the question.
Which of the following situations best exemplifies “collaboration,” where individuals work together to achieve a common goal?
Cho hàm số \(f(x)\) liên tục trên R thỏa mãn \(\int_{-1}^8 f(x)dx=-1\) và \(\int_{4}^8 f(x)dx = 4\). Giá trị của \(P = \int_{-1}^4 f(x)dx\) bằng bao nhiêu?
Các loại đường tự nhiên như mật ong, đường có trong trái cây,... thường chứa các dưỡng chất bổ sung như vitamin, khoáng chất và chất xơ. Chất xơ đặc biệt quan trọng, giúp làm chậm quá trình hấp thụ đường, giảm tác động tiêu cực lên mức đường trong máu và giúp cải thiện sức khoẻ đường ruột. Tiến hành phân tích 250 mL một mẫu nước ép cam tươi có hàm lượng đường như sau:
Thành phần
Phần trăm khối lượng
Fructose
2,5%
Glucose
2,0%
Biết khối lượng riêng của nước ép cam tươi là \(1,05 \mathrm{~g} / \mathrm{mL}\). Lượng đường có trong 250 mL mẫu nước ép cam tươi trên là
Dựa theo cấu hình electron, các nguyên tố hóa học được phân loại thành
Read the following passage about food addiction and mark the letter A, B, C, or D on your answer sheet to indicate the best answer to each of the following questions from 31 to 40.
Few people would disagree that one of the world's most popular dishes is pizza. Twenty-two-year-old Zack certainly wouldn't. He would eat a variety of pizza-based items, including homemade pizza, precooked microwave pizza, and even pizza leftovers from the night before. He was consuming 800kg of pizza a year. As a child, Zack had eaten a wide variety of food. But he became addicted to pizza when he started secondary school. American school meals have often been criticised for the large amount of fast food present on the menu, and pizza is the star dish. Zack even spent all his pocket money on slices of pizza.
Naturally, Zack's family worried about his high-calorie, low-vitamin diet. So did Zack. In an attempt to break his addiction, Zack agreed to appear on a TV programme called Freaky Eaters. Its aim was to encourage food addicts to beat their addictions with the help of a psychologist and nutritionist. It wasn't easy. He had to eat a fish dish, while his brother sat in front of him enjoying... a pizza! However, Zack met the challenge and has never eaten pizza again.
Seventeen-year-old Stacy Irvine's friends visit her and discover that she has been rewarded thousands of free toys from fast food restaurants as a regular customer. Stacy's mother often gave her two-year-old girl a portion of fried chicken in a McDonald's restaurant. [I] Since then, Stacy has refused to eat anything else except for pieces of fried chicken, and as a result, her diet has created serious health. She has been warned that if she doesn't change her diet, she will die. [II] Stacy once collapsed due to lack of vitamins and nutrients and needed to be hospitalised. [III] She insisted that Stacy adopt a healthier lifestyle. However, worryingly, Stacy's mother said that while Stacy was beginning to understand the seriousness of her situation, she couldn't eat anything else but chicken nuggets. [IV]
Twenty-year-old Hanna Little was keen on chips. The only thing that Hanna consumed for fifteen years was one plate of chips after another. Not surprisingly, a diet that contained few nutrients and an excess of fat and carbohydrates could only have negative consequences. And it did because not only did Hanna develop health problems, but she also had to leave her job after collapsing at work. At five, Hanna became addicted to chips and refused to eat fruits and vegetables despite her mother's efforts. Hanna says that she was terrified of tasting the flavour of different types of food and she would feel anxious just at the idea of doing it. Parties, picnics and barbecues with friends and family used to be a nightmare. Furthermore, Hanna was soon seen as 'odd' by her friends' parents.
It wasn't until the age of sixteen that Hanna realised she had Selective Eating Disorder (SED). Despite this new knowledge, no solution was found. It wasn't until she lost her job before she started eating normally. Hanna sought therapy from psychologist Felix Economakis, who used hypnosis, a treatment that none of the doctors that she had seen before had mentioned, to get her to eat fruit after one one-hour session, and since then she has been willing to eat anything.... including chips!
(Adapted from Friends Global)
The phrase addicted to in paragraph 1 could be best replaced by _____.