Vật A có khối lượng gấp hai lần vật B. Ném hai vật theo phương ngang với cùng tốc độ đầu ở cùng một vị trí. Nếu bỏ qua mọi lực cản thì
A. vị trí chạm đất của vật A xa hơn vị trí chạm đất của vật B.
B. vị trí chạm đất của vật B xa hơn vị trí chạm đất của vật A.
C. vật A và B rơi cùng vị trí.
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Thời gian rơi $t$ chỉ phụ thuộc vào độ cao $h$ của vật so với mặt đất, được tính bởi $t = \sqrt{\frac{2h}{g}}$.
Vì hai vật được ném từ cùng một vị trí (cùng độ cao $h$) với cùng vận tốc đầu $v_0$, nên thời gian rơi $t$ của hai vật bằng nhau, và do đó tầm xa $L$ của hai vật cũng bằng nhau. Khối lượng của vật không ảnh hưởng đến vị trí chạm đất.
Vậy vật A và vật B rơi cùng vị trí.
Câu hỏi liên quan
Từ năm 1986 đến nay, Việt Nam
Một nhóm học sinh thực hiện thí nghiệm tìm hiểu về hiện tượng cảm ứng điện từ như sau: dùng một cuộn dây có hai đầu dây nối vào điện kế G, đặt một nam châm thẳng dọc theo trục của cuộn dây như hình vẽ.
Mark the letter A, B, C or D to indicate the best arrangement of utterances or sentences to make a meaningful exchange or text in each of thefollowing questions from 25 to 29.
a. From 1960 to 1980, the rural population declined gradually.
b. The line graph shows Vietnam's urban population steadily increased from 1960 to 2020 while the rural population decreased.
c. In 1960, most Vietnamese people lived in rural areas.
d. By contrast, the urban population rose throughout the same period, from 15% to 19%.
e. In a period of 40 years, it continued to grow, reaching 37% by 2020.
Taking selfies, a cultural phenomenon, (18) ______. A selfie is a self-portrait taken with a smartphone or camera. This trend has gained immense popularity, especially among younger generations, (19) ______. The ease of taking and sharing selfies has made them a staple in modern communication.
Selfies serve various purposes beyond just capturing images. (20) ______. Additionally, selfies can be a form of self-expression, as individuals often choose specific angles, filters, and settings to convey their mood or personality. This ability to curate one’s image has led to the rise of social media influencers who rely on selfies to connect with their audiences and promote brands.
However, the selfie trend is not without its criticisms. Constantly judged by others on social media, (21) ______. Some argue that the obsession with selfies can lead to unrealistic
beauty standards and a distorted self-image. (22) ______.
Read the following passage about taking selfies 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 18 to 22.
Read the following leaflet 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 7 to 12.
MAKE A DIFFERENCE IN THE LIVES OF ANIMALS!
Animal shelters depend on the kindness of volunteers to care for homeless animals.
♻ Why Volunteer?
Many animals in shelters have been abandoned by their owners while (7) _______are rescued from dangerous situations. By volunteering, you can help provide food, medical care, and comfort to animals in need.
♻ How You Can Help:
Spend time with the animals, ensuring they feel loved and safe. Assist with cleaning and maintaining shelter facilities, as failing to tidy up messes can (8) _______ unhealthy conditions. Help raise awareness about adoption programs and the importance of reducing the (9) _______ of homeless animals. Rather than adopt a new pet without preparation, educate potential owners about proper care as many animals suffer neglect and abandonment (10) _______ irresponsible ownership. Together, we can ensure that every animal has a chance at a better (11) _______.
♻ Get Involved Today!
Volunteering doesn’t just benefit the animals - it gives you a sense of fulfillment and the opportunity to meet others who share the same (12) _______.
- Chỉ số hay độ
của một dung dịch được tính theo công thức
với
là nồng độ ion hydrogen. Độ
của một loại nước ngọt có
là bao nhiêu?
- Trong không gian với hệ tọa độ
, phương trình nào sau đây là phương trình tham số của đường thẳng?
Hình ảnh dưới đây mô tả ảnh hưởng của nhân tố tiến hóa nào?
Nội dung nào sau đây là một trong những tác động tích cực của các cuộc cách mạng công nghiệp thời kì hiện đại đối với xã hội?
Cho h = 6,625.10-34 J.s và c = 3.108 m/s. Một kim loại có công thoát A = 5,68.10-19 J thì giới hạn quang điện là
Twenty-three years later, she was _____________ to get a reply from someone in the Netherlands.
Cho các phát biểu sau
(a) Những nguyên tử có cùng số electron thuộc cùng một nguyên tố hóa học.
(b) Hai nguyên tử A và B đều có số khối là 14. Vậy hai nguyên tử này thuộc cùng một nguyên tố hóa học.
(c) Những nguyên tử có cùng số neutron thuộc cùng một nguyên tố hóa học.
(d) Hai ion dương (ion một nguyên tử) có điện tích lần lượt là +2 và +3, đều có 26 proton. Vật hai ion này thuộc cùng một nguyên tố hóa học.
Số phát biểu đúng là
Giai cấp đông đảo nhất và giữ vai trò quan trọng nhất trong sản xuất nông nghiệp ở Trung Quốc thời kì trung đại là
Read the following passage about green living habits 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 23 to 30.
In an era marked by climate change and environmental degradation, adopting green living habits has become increasingly vital. Green living refers to a lifestyle that seeks to minimize one’s ecological footprint through conscious choices in daily activities. This can include everything from reducing waste to conserving energy and using sustainable products. As more individuals recognize the importance of preserving our planet, the movement toward greener practices continues to gain momentum.
One of the most significant aspects of green living is its focus on sustainability. By choosing products that are eco-friendly, consumers can support businesses that prioritize environmental responsibility. For instance, using reusable bags, bottles, and containers reduces plastic waste and promotes a circular economy. Furthermore, opting for locally sourced foods not only supports local farmers but also decreases the carbon emissions associated with transportation.
When green living habits are adopted, they can lead to profound changes in our environment. By reducing their energy consumption through the use of energy-efficient appliances, individuals help lower greenhouse gas emissions. Consequently, this contributes to cleaner air and mitigates the effects of climate change. Moreover, by practicing water conservation methods, such as fixing leaks and using low-flow fixtures, households can significantly decrease water waste, promoting the sustainable use of this precious resource.
In conclusion, educating individuals about green living habits is crucial for promoting a more sustainable future. Schools and community organizations can offer workshops and resources that highlight the benefits of eco-friendly practices. Additionally, social media campaigns can raise awareness and encourage people to share their experiences with sustainable living. By empowering individuals to make informed choices, we can collectively work toward a healthier planet for generations to come.
The word ‘vital’ in paragraph 1 is OPPOSITE in meaning to ______.
Read the following leaflet 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 35 to 40.
How to Live Your Life Actively?
If you are not naturally sporty, and finding ways to fit more activity into your daily life, here are several tips to help you make a routine (35) ____________ being active:
Select a realistic exercise plan.
Track your progress using a health app (36) ____________ a paper checklist.
Take every opportunity to do such strength-building activities as carrying (37) ____________ and climbing the stairs.
Invite friends and (38) ____________ family members to join in, and try (39) ____________ everyone's competitive side with challenges like seeing who can do the most steps or cover the most distance in a day.
Reward yourself with a treat like a favourite TV show if your plan works (40) ____________ to maintain your motivation.
(Adapted from https://www.nhs.uk)
Choose the best answer for number 35:
Với số nguyên dương \(n\), gọi \(a_{3 n-3}\) là hệ số của \(x^{3 n-3}\) trong khai triển thành đa thức của \(\left(x^{2}+1\right)^{n}(x+2)^{n}\). Tìm \(n\) để \(a_{3 n-3}=26 n\).
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.
Taking Home the World Cup
Standing just 36 centimeters tall, the FIFA World Cup Trophy symbolizes the pinnacle of football achievement. Every four years, teams worldwide compete for it, but no one ever takes the trophy home. Made of 18-carat gold, the original trophy remains under FIFA's protection, with winners receiving only a replica. This measure safeguards it from theft, as the trophy has been stolen twice in its history.
The original trophy was made by a French sculptor, Abel LaFleur, and was called the “Jules Rimet Cup,” in honor of the founder of the World Cup tournament. Sometime during the first three World Cup events (1930, 1934, and 1938), the name changed to simply the “World Cup.” Then during World War II, not much was seen or heard of the trophy. It was being kept hidden in a shoe box under the bed of Dr. Ottorino Barassi, the Italian vice-president of FIFA, to prevent it from falling into the hands of the Nazi army. In 1966, the Cup was stolen during a public showing of the trophy prior to the World Cup tournament in England. Luckily, it was found a short time later, none the worse for wear, in a trash container by a little dog named Pickles. Four years later, Brazil earned permanent possession of the original trophy by winning its third World Cup title. Unfortunately, the trophy was stolen a second time in 1983 and was never recovered. The Brazilian Football Association had to have a duplicate trophy made.
(I) After the first trophy became the possession of Brazil’s football association, a new World Cup Trophy for FIFA was designed by an Italian artist, Silvio Gazzaniga, in 1974. (II) This trophy cannot be won outright, but remains in the possession of FIFA, and rest assured they are watching it very closely. Today, World Cup winners are awarded a replica of the trophy that is gold-plated, rather than solid gold like the real one. (III) Gazzaniga’s World Cup trophy weighs almost five kilograms. (IV) Its base contains two layers of a semi-precious stone called malachite, and has room for seventeen small plaques bearing the names of the winning teams---enough space to honor all the World Cup champions up to the year 2038. After that, a new trophy will have to be made.
The phrase "none the worse for wear" could best be replaced by:
Giá trị nghệ thuật của văn bản Ra-ma buộc tội là gì?
Bộ ba nào quy định mã mở đầu tổng hợp aa mở đầu ở sinh vật nhân thực?
Trong quá trình phát sinh và phát triển sự sống trên Trái Đất, ở kỉ nào sau đây xảy ra sự phát sinh thú và chim?