tailieunhanh - Đề thi đại học môn Tiếng anh năm 2013 - Mã đề 693 - Khối A

Tham khảo đề thi - kiểm tra 'đề thi đại học môn tiếng anh năm 2013 - mã đề 693 - khối a', tài liệu phổ thông, ôn thi đh-cđ phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Bộ GIÁO ĐỤC VÀ ĐÀO TẠO ĐẺ CHÍNH THỪC De cỏ 6 trang ĐẺ THI TUYẺN SINH OẠI HỌC NĂM 2013 Mỏn TIẾNG ANH Khối AI Thời gian làm bài 90 phía không kè thời gian phát đề Mìi đề thỉ 693 Họ tên thí sinh . số báo danh . ĐỀ THI GÒM 80 CÂU TỪ QUESTION 1 f ẺN QUESTION 80 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 from Ỉ to io. Archimedes Principle is a law of physics that states that when an object is totally or partially immersed in a fluid it experiences an upthrust equal to the weight of the fluid displaced. The principle is most frequently applied to the behaviour of objects ill water and helps to explain floating and sinking and why objects seem lighter in waler. 11 also applies to balloons. The key word in the principle is upthrust which refers to the force acting upward to reduce the apparent weight of the object when it is under water. If for example a metal block with a volume of 100 cm is dipped in water it displaces an equal volume of water which has a weight of approximately I N oz . The block therefore seems to weigh about I N less. An object will float if its average density is less than that of water. If it is totally submerged the weight of the water it displaces and hence the upthrust on it is greater than its own weight and it is forced upward and out of the water until the weight of the water displaced by the submerged part is exactly equal to the weight of the floating object. Thus a block of wood with a density six tenths that of water will float with six tenths of its volume under water since at that point the weight of fluid displaced is the same as the block s own weight. If a dense material is made into a suitable shape it win float because of Archimedes principle. A ship floats whereas a block of iron of the same mass sinks. Il is also because of Archimedes principle that ships float lower in the water when they arc heavily loaded more water must be displaced