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6 tháng 4 2015

Hiệu cân nặng giữa John và Sarah là:

67,5 - 26,5 = 41 (pound)

Nếu cân ngặn của cả John và Sarah cùng bớt đi x pound thì Sarah nặng bằng 1/3 John. Hiệu số phần bằng nhau là:

3 - 1 = 2 (phần)

Mà khi bớt đi ở cả hai số cùng 1 giá trị thì hiệu của chúng vẫn bằng nhau do đó 2 phần ứng với 41 pound. Vậy 1 phần ứng với:

41 : 2 = 20,5 (pound)

Vậy giá trị của x là:

 26,5 - 20,5 = 6 (pound)

12 tháng 2 2017

cha mạ mi thằng điên

12 tháng 2 2017

dịch: cân nặng của 3 quả táo bằng 4 quả chuối, cân nặng 5 quả chuối bằng 6 quả cam. Hỏi có bao nhiều quả táo để có cân nặng bằng với 24 quả cam?
giải: Ta có: 24 quả cam = 20 quả chuối (đều x4)
                 20 quả chuối = 15 quả táo (đều x5)
=> Cân nặng của 15 quả táo sẽ bằng cân nặng của 24 của cam.

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        Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water....
Đọc tiếp

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

       Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water. It 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 cmis dipped in water, it displaces an equal volume of water, which has a weight of approximately 1 N (3.5 oz). The block therefore seems to weigh about 1 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 water, until the weight if water displaced by 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 blocks’s own weight. If a dense material is made into a suitable shape, it will float because of Archimedes’s principle. A ship floats, whereas a block of iron of the same mass sinks.

        It is also because of Archimedes’s principle that ships float lower in the water when they are heavily loaded (more water must be displaced to give the necessary upthrust). In addition, they cannot be so heavily loaded if they are to sail in fresh water as they can if they are to sail in the sea, since fresh water is less dense than sea water, and so more water must be displaced to give the necessary upthrust. This means the ship is lower in the water, which can be dangerous in rough weather.

         From “Archimedes’s Principle”, MicrosoftÒ Student 2008[DVD]. Microsoft Corporation, 2007.

Archimedes’ Principle explains why ____

A. all objects will float

B. Archimedes became 

C. objects seem lighter in water

D. humans can swim

1
22 tháng 6 2019

Đáp án C

C. objects seem lighter in water: Định lí Archimedes giải thích tại sao: các vật thể có thể nhẹ hơn nước.

Chúng ta có thể tìm thấy ý này trong câu hai của đoạn một : “The principle is most frequently applied….and why objects seem lighter in water”.

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        Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water....
Đọc tiếp

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

       Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water. It 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 cmis dipped in water, it displaces an equal volume of water, which has a weight of approximately 1 N (3.5 oz). The block therefore seems to weigh about 1 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 water, until the weight if water displaced by 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 blocks’s own weight. If a dense material is made into a suitable shape, it will float because of Archimedes’s principle. A ship floats, whereas a block of iron of the same mass sinks.

        It is also because of Archimedes’s principle that ships float lower in the water when they are heavily loaded (more water must be displaced to give the necessary upthrust). In addition, they cannot be so heavily loaded if they are to sail in fresh water as they can if they are to sail in the sea, since fresh water is less dense than sea water, and so more water must be displaced to give the necessary upthrust. This means the ship is lower in the water, which can be dangerous in rough weather.

         From “Archimedes’s Principle”, MicrosoftÒ Student 2008[DVD]. Microsoft Corporation, 2007.

A block of wood with a density seven tenths that of water will ____

A. go up and down the sink

B. float with a half of its volume under water

C. float with an equal volume of its volume under water

D. sink immediately when submerged

1
26 tháng 2 2019

Đáp án C

C. float with an equal volume of its volume under water

Ý nghĩa của cả câu: “Một khối gỗ có tỉ trọng bảy phần mười tỉ trọng của nước sẽ nổi lên với một thể tích tương đương với thể tích chìm của nước”.

Chúng ta có thể tìm thấy ý này trong câu ba của đoạn 3: “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 displaces is the same as the block’s own weight”.

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        Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water....
Đọc tiếp

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

       Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water. It 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 cmis dipped in water, it displaces an equal volume of water, which has a weight of approximately 1 N (3.5 oz). The block therefore seems to weigh about 1 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 water, until the weight if water displaced by 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 blocks’s own weight. If a dense material is made into a suitable shape, it will float because of Archimedes’s principle. A ship floats, whereas a block of iron of the same mass sinks.

        It is also because of Archimedes’s principle that ships float lower in the water when they are heavily loaded (more water must be displaced to give the necessary upthrust). In addition, they cannot be so heavily loaded if they are to sail in fresh water as they can if they are to sail in the sea, since fresh water is less dense than sea water, and so more water must be displaced to give the necessary upthrust. This means the ship is lower in the water, which can be dangerous in rough weather.

         From “Archimedes’s Principle”, MicrosoftÒ Student 2008[DVD]. Microsoft Corporation, 2007.

Ships cannot be so heavily loaded if they want to sail in fresh water as they sail in the sea, because ____

A. fresh water is ‘lighter’ than sea water

B. there’s too much salt in sea water 

C. sea water is ‘saltier’ than fresh water

D. fresh water is more polluted

1
13 tháng 12 2019

Đáp án A

A. fresh water is ‘lighter’ than sea water: ý nghĩa của cả câu này là “Tàu thuyền không thể được chất nặng khi chúng đi trên sông như khi chúng đi trên biển, bởi vì nước sông thì nhẹ hơn nước biển”.

Chúng ta có thể tìm thấy ý này trong câu hai của đoạn bốn: “In addition, they cannot be so heavily loaded….to give the necesssary upthrust”

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        Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water....
Đọc tiếp

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

       Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water. It 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 cmis dipped in water, it displaces an equal volume of water, which has a weight of approximately 1 N (3.5 oz). The block therefore seems to weigh about 1 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 water, until the weight if water displaced by 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 blocks’s own weight. If a dense material is made into a suitable shape, it will float because of Archimedes’s principle. A ship floats, whereas a block of iron of the same mass sinks.

        It is also because of Archimedes’s principle that ships float lower in the water when they are heavily loaded (more water must be displaced to give the necessary upthrust). In addition, they cannot be so heavily loaded if they are to sail in fresh water as they can if they are to sail in the sea, since fresh water is less dense than sea water, and so more water must be displaced to give the necessary upthrust. This means the ship is lower in the water, which can be dangerous in rough weather.

         From “Archimedes’s Principle”, MicrosoftÒ Student 2008[DVD]. Microsoft Corporation, 2007.

A ship floats, whereas a block of iron of the same mass sinks because the ship ____

A. is made of wood

B. is lighter

C. has buoys 

D. has a special shape

1
5 tháng 5 2019

Đáp án D

D. has a special shape: ý nghĩa cả câu này: “Một chiếc tàu nổi bềnh bồng trong khi một khối sắt có trọng lượng giống như thế thì chìm bởi vì chiếc tàu có hình dáng đặc biệt”.

Chúng ta có thể tìm thấy ý này trong hai câu cuối của đoạn 3: “If a dense material is made into a suitable shape, it will float because of Archimedes’ principle. A ship floats, whereas a block of iron of the same mass sinks”.

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        Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water....
Đọc tiếp

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

       Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water. It 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 cmis dipped in water, it displaces an equal volume of water, which has a weight of approximately 1 N (3.5 oz). The block therefore seems to weigh about 1 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 water, until the weight if water displaced by 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 blocks’s own weight. If a dense material is made into a suitable shape, it will float because of Archimedes’s principle. A ship floats, whereas a block of iron of the same mass sinks.

        It is also because of Archimedes’s principle that ships float lower in the water when they are heavily loaded (more water must be displaced to give the necessary upthrust). In addition, they cannot be so heavily loaded if they are to sail in fresh water as they can if they are to sail in the sea, since fresh water is less dense than sea water, and so more water must be displaced to give the necessary upthrust. This means the ship is lower in the water, which can be dangerous in rough weather.

         From “Archimedes’s Principle”, MicrosoftÒ Student 2008[DVD]. Microsoft Corporation, 2007.

What happens when something is immersed in a fluid?

A. It will be pushed further down with a force, equal to the weight of the fluid displaced.

B. It receives an upward force, equal to the weight of the fluid displaced

C. It receives a download force, equal to the weight of the fluid displaced

D. The fluid will expand the object and overflow to the floor

1
26 tháng 5 2018

Đáp án B

It receives an upward force, equal to the weight of the fluid displaced: “Nó nhận một lực đẩy lên tương đương với trọng lượng của chất lỏng bị chiếm chỗ”.

Câu này thích hợp với câu hỏi: “Điều gì xảy ra khi một vật nào đó nổi lên trong một chất lỏng?”

Chúng ta có thể tìm thấy ý này trong câu đầu của đoạn một: “Archimedes’s 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.”

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        Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water....
Đọc tiếp

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

       Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water. It 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 cmis dipped in water, it displaces an equal volume of water, which has a weight of approximately 1 N (3.5 oz). The block therefore seems to weigh about 1 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 water, until the weight if water displaced by 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 blocks’s own weight. If a dense material is made into a suitable shape, it will float because of Archimedes’s principle. A ship floats, whereas a block of iron of the same mass sinks.

        It is also because of Archimedes’s principle that ships float lower in the water when they are heavily loaded (more water must be displaced to give the necessary upthrust). In addition, they cannot be so heavily loaded if they are to sail in fresh water as they can if they are to sail in the sea, since fresh water is less dense than sea water, and so more water must be displaced to give the necessary upthrust. This means the ship is lower in the water, which can be dangerous in rough weather.

         From “Archimedes’s Principle”, MicrosoftÒ Student 2008[DVD]. Microsoft Corporation, 2007.

The word “upthrust” in the passage refers to the _____

A. upward push

B. upper side of an object

C. upturned force

D. upside-down turn

1
31 tháng 7 2019

Đáp án A

A. upward push: từ “upthrust” trong đoạn bốn đề cập đến “lực đẩy từ dưới lên = upward push”.

Còn các đáp án khác

Câu B “upperside of an object”: phía bên trên của một vật.

Câu C “upward force”: lực làm lật tàu, thuyền.

Câu D “upside-down turn”: việc lật lại từ trên xuống dưới.

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        Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water....
Đọc tiếp

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

       Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water. It 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 cm3  is dipped in water, it displaces an equal volume of water, which has a weight of approximately 1 N (3.5 oz). The block therefore seems to weigh about 1 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 water, until the weight if water displaced by 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 blocks’s own weight. If a dense material is made into a suitable shape, it will float because of Archimedes’s principle. A ship floats, whereas a block of iron of the same mass sinks.

        It is also because of Archimedes’s principle that ships float lower in the water when they are heavily loaded (more water must be displaced to give the necessary upthrust). In addition, they cannot be so heavily loaded if they are to sail in fresh water as they can if they are to sail in the sea, since fresh water is less dense than sea water, and so more water must be displaced to give the necessary upthrust. This means the ship is lower in the water, which can be dangerous in rough weather.

         From “Archimedes’s Principle”, MicrosoftÒ Student 2008[DVD]. Microsoft Corporation, 2007.

The word “volume” in the passage refers to ______.

A. loudness

B. quantity

C. frequency

D.  lenght

1
27 tháng 3 2018

Đáp án B

B. quantity: từ “quantity” có nghĩa là “số lượng”.

Cụm từ “a volume of water” trong đoạn hai có nghĩa là “một lượng nước”.

Câu A “loudness” có nghĩa là “độ lớn của âm thanh”.

Câu C “frequency” có nghĩa là “tần suất”.

Câu D “length” có nghĩa là “độ dài”.

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        Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water....
Đọc tiếp

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

       Archimedes’s 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 in water, and helps to explain floating and sinking, and why objects seem lighter in water. It 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 cmis dipped in water, it displaces an equal volume of water, which has a weight of approximately 1 N (3.5 oz). The block therefore seems to weigh about 1 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 water, until the weight if water displaced by 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 blocks’s own weight. If a dense material is made into a suitable shape, it will float because of Archimedes’s principle. A ship floats, whereas a block of iron of the same mass sinks.

        It is also because of Archimedes’s principle that ships float lower in the water when they are heavily loaded (more water must be displaced to give the necessary upthrust). In addition, they cannot be so heavily loaded if they are to sail in fresh water as they can if they are to sail in the sea, since fresh water is less dense than sea water, and so more water must be displaced to give the necessary upthrust. This means the ship is lower in the water, which can be dangerous in rough weather.

         From “Archimedes’s Principle”, MicrosoftÒ Student 2008[DVD]. Microsoft Corporation, 2007.

The word “displaces” in the passage almost means “_____”

A. takes the place of        

B. takes place

C. replaces with a new one

D. puts in position

1
17 tháng 8 2019

Đáp án A

A. takes the place of: động từ “displaces” trong đoạn ba có nghĩa là “chiếm chỗ của”.

Còn các đáp

Câu B “takes places” có nghĩa là “xảy ra”.

Câu C “replaces with a new one = thay thế bằng một cái mới”, không đúng với ý nghĩa trong câu.

Câu D “puts in position” có nghĩa là “đặt vào vị trí”.