Mạch điện xoay chiều gồm RLC mắc nối tiếp, có R = 30 Ω, ZC = 20 Ω, ZL = 60Ω. Tổng trở của mạch là?
Mạch điện xoay chiều gồm RLC mắc nối tiếp, có R = 30 Ω, ZC = 20 Ω, ZL = 60Ω. Tổng trở của mạch là?
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Trong đó:
- $R$ là điện trở thuần
- $Z_L$ là cảm kháng
- $Z_C$ là dung kháng
Thay số vào, ta có:
$Z = \sqrt{30^2 + (60 - 20)^2} = \sqrt{30^2 + 40^2} = \sqrt{900 + 1600} = \sqrt{2500} = 50 \Omega$.
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Các thiết bị bên trong máy tính gồm?
Read thefollowing passage and mark the letter A, B, C or D on your answer sheet to indicate the option that bestfits each of the numbered blanksfrom 18 to 22.
Peer pressure, (18) ________, can have both positive and negative effects. For instance, when surrounded by motivated peers, (19) ________. Positive peer pressure can be a great motivator, as peers who excel in academics or extracurricular activities can inspire others to follow suit. However, peer pressure can also lead to negative outcomes. The influence of friends who engage in risky behaviors, such as skipping school or using substances, can encourage others to make poor decisions. Studies have shown that teenagers are more likely to take risks in the presence of their peers because they feel more confident when surrounded by others.
While peer pressure is often associated with negative behavior, (20) ________. For example, students may be encouraged to excel in their studies or participate in volunteer activities due to the positive influence of their peers. However, it is important to develop strong decision-making skills and self-confidence (21) ________.
Parents and educators play a key role in helping young people navigate peer pressure. By teaching young people how to recognize both positive and negative peer pressure, and how to make independent, thoughtful decisions, parents and educators can help ensure that students thrive in a healthy, supportive environment. Encouraging open communication, providing advice on how to stay true to one's values, and helping students develop self-confidence are all crucial aspects of this process.
In conclusion, peer pressure is a powerful influence. (22) ________, teenagers can succeed and grow in a positive social environment.
Có bao nhiêu phép ghép các đối tượng đồ họa?
Khi biên dịch chương trình trên Arduino IDE có lỗi xuất hiện như hình dưới.
Nguyên nhân của lỗi này là
Healthy mind, healthy body
“A healthy mind lives in a healthy body” is a saying (1) ______ to have often been used by the ancient Greeks. Thousands of years later, the same idea still applies. According to health experts, it’s advisable (2) ______ eight to ten glasses of water every day. However, water itself is not enough; a balanced diet is essential, too. A healthy body naturally is the result of doing exercise. Many people, however, do not like gyms and object to going there for different reasons. Some, for instance, say that aerobic sessions are too difficult to follow while others say that gyms are just too expensive. Many people also say that they have (3) ______ in finding time to exercise due to their busy lifestyle, but the truth is that everyone can make a little time every now and then. Regardless of the way people choose to exercise, it is important to remember that there’s no point (4) ______ doing it only for a short period of time. Last but not least, (5) ______ a positive attitude and doing away with negative thoughts contribute to one’s good health. In short, following (6) ______ surely helps in having a healthy mind and body.
Read the following advertisement and mark the letter A, B, C, or D on your answer sheet to indicate the option that best fits each of the numbered blanks from 1 to 6.
Hóa học có vai trò quan trọng trong
Theo phạm vi của quan hệ mua bán, giao dịch, có
Cho dãy số (un) là một cấp số cộng có u1=3 và công sai d=4. Giá trị của u5 bằng
Cho các chất: ethanol (), acetaldehyde (CH3CHO), acetone (CH3COCH3) , glucose , fructose , maltose , saccharose Có bao nhiêu chất phản ứng được với thuốc thử Tollens sinh ra bạc?
Chủ thể trong nền kinh tế thị trường định hướng xã hội chủ nghĩa, Nhà nước có vai trò quản nền kinh tế thông qua thực hiện chức năng quản lí nhà nước về kinh tế được gọi là gì?
Trên hình chiếu phối cảnh, đường chân trời là:
Cho biết nguyên tử khối: H = 1; C = 12; N = 14; O = 16; Na = 23; Al = 27; S = 32; Fe = 56; Ba = 137.
- Thao tác nào sau đây cần thực hiện khi cần kết nối điện thoại thông minh với bộ thu phát Wi-fi (Wi-fi Access Point)?
Một quần thể người đang ở trạng thái cân bằng di truyền, tần số người bị mắc một bệnh di truyền đơn gene là 9%. Phả hệ dưới đây cho thấy một số thành viên (màu đen) bị một bệnh này. Kiểu hình của người có đánh dấu ? là chưa biết.
Xác suất người con (III-?) bị bệnh là bao nhiêu?
Read the passage carefully. Choose an option (A, B, C or D) that best answers each question from 16 to 22.
1. Like many emergency responders, Nicholas Groom is used to stress at work. On the one hand, the stress can be helpful. “I find that when attending a serious incident, it helps me to maintain focus on the situation,” Nicholas Groom said. On the other hand, the work can be highly pressurized. “Too much stress can impair your ability to make decisions,” he adds. And Groom is not alone in his complicated relationship with stress.
2. Many people believe that there should be a balanced amount of stress. In other words, not too much stress so you’re not overwhelmed but not too little stress so you don’t feel unmotivated. After all, some anxiety is motivating; think of the adrenaline before a deadline or the excitement before a competition. Sports fans sometimes even talk about a “gene” in some athletes who seem to play best in the decisive final moments of a match. Furthermore, many psychologists claim that performance in many situations increases with stress up to a point. Of course, any stress can cause harm when it’s prolonged. To take just one example, a long-term high heart rate is linked to cardiovascular diseases. And additional stressors, such as financial pressures or psychiatric issues, clearly affect how beneficially someone can respond to stress.
3. So is there a way to harness stress to your advantage while being mindful of its detrimental long-term effects? One key factor is to avoid, whenever possible, the point when stress leads to mental and physical collapse. Crystal Wernicke, 30, has always used stress as a motivator. But juggling between parenting, a full-time job, a voluntary role and financial troubles at the same time became too much and eventually led to a two-month period of illness. Another factor is the presence of control. For those who feel powerless over their situation, stress is unlikely to be beneficial. But with some autonomy over stressful tasks, we are better able to convert that pressure into higher performance.
4. When it comes to stress and how it affects your performance, it’s helpful to recognize the variations in personality, type of stress and task that affect the level of pressure you are under, as well as understanding tools you can use to control and harness that stress. Ultimately, it’s not helpful to take a one-sided view, either demonizing or glorifying stress. As James C Quick, a management professor at the University of Texas, sums up: “Stress can be the kiss of death as well as the spice of life.”
What is “detrimental” in paragraph 3 closest in meaning to?
Cho hình lăng trụ tam giác \(ABC\cdot A'B'C'\).
Read the following passage about the Reimagining International Cooperation 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.
Global environmental governance is changing how countries work together. Nations now understand that pollution, climate change, and resource problems cross borders. Traditional agreements between countries are not enough anymore. New approaches include businesses, local communities, and citizen groups working with governments. This all-hands-on-deck approach helps create better solutions for our planet. Many successful projects show that when different groups cooperate, they can solve difficult environmental problems that single countries cannot fix alone.
Environmental governance faces many challenges today. [I] Political differences between nations often slow down important decisions. [II] Some countries worry that strict environmental rules might hurt their economic growth. Despite these obstacles, new technologies are helping countries monitor environmental changes better. [III] Satellite data and computer models allow scientists to track forest loss, ocean pollution, and climate patterns. [IV] This information helps leaders make smarter decisions about protecting natural resources.
The future of environmental governance depends on innovation. Digital platforms now connect environmental experts around the world instantly. Young people are bringing fresh ideas through social media campaigns and protest movements. Indigenous communities contribute valuable traditional knowledge about sustainable living practices. Financial institutions are creating new ways to fund green projects in developing countries. These combined efforts are creating a more flexible and responsive system of global cooperation that can adapt to changing environmental conditions more quickly than old-fashioned diplomatic channels.
Effective environmental governance requires balance between global standards and local solutions. While international agreements provide important frameworks, communities need freedom to implement approaches that fit their unique situations. Successful governance models respect cultural differences while maintaining scientific standards. Education plays a crucial role in building public support for environmental policies. When citizens understand environmental issues, they make better choices and hold their leaders accountable. The most promising path forward combines strong international institutions with energetic local action to create lasting environmental solutions.
Which of the following is TRUE according to the passage?
Đơn vị lưu trữ dữ liệu lớn nhất là
Hình ảnh nào sau đây thể hiện vai trò cung cấp nguyên liệu chế biến của ngành trồng trọt?