Dựa theo đồ thị (d-t) ở hình bên, hãy xác định tốc độ tức thời của vật tại vị trí B
Dựa theo đồ thị (d-t) ở hình bên, hãy xác định tốc độ tức thời của vật tại vị trí B
Hãy suy nghĩ và trả lời câu hỏi trước khi xem đáp án
Tại điểm B, đồ thị nằm ngang, có nghĩa là độ dốc bằng 0. Do đó, tốc độ tức thời tại B là $0 m/s$.
Câu hỏi liên quan
Các tổ chức, cá nhân giữ vai trò kết nối giữa người tiêu dùng và người sản xuất trong nền kinh tế được gọi là gì?
Cỏ dại quen nắng mưa
Làm sao mà giết được
Tới mùa nước dâng
Cỏ thường ngập trước
Sau ngày nước rút
Cỏ mọc đầu tiên…
Trong cuộc đời bình yên tựa nghìn xưa
Gần gũi nhất vẫn là cây lúa
Trưa nắng khát ước về vườn quả
Lúc xa nhà nhớ một dáng mây
Một dòng sông, ngọn núi, rừng cây
Một làn khói, một mùi hương trong gió…
Có mấy ai nhớ về ngọn cỏ
Mọc vô tình trên lối ta đi
Dẫu nhỏ nhoi không đáng nhớ làm chi
Không nghĩ đến nhưng mà vẫn có.
(Xuân Quỳnh, Cỏ dại, dẫn theo thivien.net)
Hình tượng trung tâm được khắc họa trong đoạn thơ trên là?
Read the following passage about managing change 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.
Growing up in Athens, Greece, Lydia Borsi remembers feeling tested when she tried to deal with mental health issues. Borsi says she had been seeing a therapist for anxiety. But she notes that people in Greece do not openly discuss mental health issues, which also get little attention in general healthcare services. “It was a lot more secretive. And people thought that I was a lot more unique,” Borsi said.
That all changed in 2017 when she moved to the United States to study at the University of Rochester in Rochester, New York. “When I came here, I really liked that people were not afraid to speak up about mental health and say that it’s important,” she said. The university was very supportive of her needs and offered plenty of information. She also became involved with a school group called Active Minds that helps students deal with mental health issues. [A]
Then due to the spread of the novel coronavirus, the University of Rochester had to move all its classes and some of its mental health resources online. Luckily, Borsi was able to connect with a mental health expert outside the school, in the local community. [B]
But as many of her American friends returned home, Borsi was stuck. Greece had succeeded in limiting the spread of the virus within its borders, but flights there from the U.S. are barred until July. Also, the health crisis has put her plans to seek admission to medical school in Britain on hold. [C] And she is not alone.
[D] In April, Active Minds launched a survey of over 2,000 students at U.S. colleges and universities. The study found that over 80 percent of those asked said the coronavirus crisis had negatively affected their mental health. One in five said it has affected them severely.
Laura Horne, chief program officer at Active Minds, says the findings are especially troubling given that the crisis is only going to make it harder for colleges and universities to help these students. “Colleges and universities had to pivot rather quickly to respond to COVID-19 and figure out all facets of university life, including mental health services. Now they have to figure out how to communicate with students,” Horne said.
Frank Chen is a Houston, Texas-based psychiatrist who has worked with college-age young adults. He points out that individuals at that age are in an important stage of their mental development. And college can be a difficult experience for students with or without mental health issues, as they balance work, studies, and personal relationships. Adding a major world event, like the spread of the coronavirus, makes it very difficult to predict what the long-term psychological effects might be. “I don’t think that there’s another event in the history of the people who are alive now that can really measure up to this,” said Chen.
Which of the following would be the best title for this article?
Vì sao năm 1911, Nguyễn Tất Thành quyết định ra đi tìm đường cứu nước?
Những biện pháp nào sau đây giúp hạn chế ô nhiễm môi trường không khí ở các khu đô thị có mật độ dân số cao?
1. Phân vùng hạn chế hoạt động của xe máy, thu phí phương tiện cơ giới vào một số khu vực trên địa bàn thành phố.
2. Hạn chế việc xây dựng công trình và tăng cường sử dụng nhiên liệu hoá thạch.
3. Thu gom rơm rạ, chất thải, phụ phẩm nông nghiệp, và tái chế thành các sản phẩm khác có ích.
4. Cải tiến công nghệ sản xuất và xử lí khí thải ở các làng nghề.
Phương pháp nào không phải là phương pháp do kháng sinh có chức năng?
Phần lãnh thổ trung tâm Bắc Mỹ địa hình phân hoá đa dạng được phân ra thành khu vực nào dưới đây?
Một vật có khối lượng 200g chuyển động tròn đều trên đường tròn có bán kính 50cm, với tốc độ dài 5m/s. Lực hướng tâm tác dụng vào vật là
Phát biểu nào đúng với ngành công nghiệp của Hoa Kì?
- Tia phóng xạ nào sau đây có thể đâm xuyên mạnh nhất?
Để lấy ra danh sách dữ liệu thỏa mãn một yêu cầu nào đó ta thực hiện?
Điểm nào dưới đây thuộc đồ thị hàm số \(y=-{{x}^{3}}+3{{x}^{2}}-2\)?
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.
Announcement: Volunteer Recruitment Results for Charity Organization
We are delighted to announce the results of our (1)______ for volunteers at the Charity Organization. After careful review and thoughtful consideration, we have (2)______ the conclusion that we have an enthusiastic and varied group of new volunteers ready to join us. This talented team will bring unique skills and fresh perspectives, as they plan (3)______ further our mission of community support and development, enriching the lives of those in need. The final list of selected volunteers is available at the Charity Organization’s main office, where we will also provide further information (4)_______ all selected candidates regarding their upcoming roles and responsibilities. We are (5)______for the high level of interest shown by the community and look forward to achieving positive change together. Thank you to everyone (6)______ and showing such wonderful support for our cause!
Phát biểu nào sau đây không đúng với ngoại thương?
Phát biểu nào sau đây sai?
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.
The word “instantly” in paragraph 3 is OPPOSITE in meaning to _________.
Trồng cà chua áp dụng cho loại mô hình nào sau đây?
Phương án nào sau đây chỉ ra vaccine DNA được đánh giá là an toàn hơn vaccine truyền thống?
Pha sáng của quang hợp diễn ra ở đâu?
Cần \(\mathrm{m}(\mathrm{g})\) glucose để điều chế \(\mathrm{a}(\mathrm{ml})\) ethyl alcohol \(45^{\circ}(\mathrm{D}=0,8 \mathrm{g} / \mathrm{ml})\), biết hiệu suất của phản ứng điều chế là \(75 \%\). Lượng khí \(\mathrm{CO}_{2}\) sinh ra hấp thụ hoàn toàn vào 1 lít dung dịch \(\mathrm{Ca}(\mathrm{OH})_{2} 1 \mathrm{M}\) thu được 60 gam kết tủa. Giá trị của m và a lần lượt là