Today we take electricity for granted and perhaps we do not realize just how useful this discovery has been. Steam was the first invention that replaced wind power. It was used to drive engines and was passed through pipes and radiators to warm rooms. Petrol mixed with air was the next invention that provided power. Exploded in a cylinder, it drove a motor engine, Beyond these simple and direct uses, those forms have not much adaptability.
On the other hand, we make use of electricity in thousands of ways. From the powerful voltages that drive our electric trains to the tiny current needed to work a simple calculator, and from the huge electric magnet in steel works that can lift 10 tons to the tiny electric magnet in a doorbell, all are powered by electricity. An electric current can be made with equal ease to heat a huge mass of molten metal in a furnace, or to boil a jug for a cup of coffee. Other than atomic energy, which has not as yet been harnessed to the full, electricity is the greatest power in the world. It is flexible, and so adaptable for any task for which it is wanted. It travels so easily and with incredible speed along wires or conductors that it can be supplied instantly over vast distances.
To generate electricity, huge turbines or generators must be turned. In Australia they use coal or water to drive this machinery. When dams are built, falling water is used to drive the turbines without polluting the atmosphere with smoke from coal. Atomic power is used in several countries but there is always the fear of an accident. A tragedy once occurred at Chernobyl, in Ukraine, at an atomic power plant used to make electricity. The reactor leaked, which caused many deaths through radiation.
Now scientists are examining new ways of creating electricity without harmful effects to the environment. They may harness the tides as they flow in and out of bays. Most importantly, they hope to trap sunlight more efficiently. We do use solar heaters for swimming pools but as yet improvement in the capacity of the solar cells to create more current is necessary. When this happens, electric cars will be viable and the world will rid itself of the toxic gases given off by trucks and cars that burn fossil fuels.
What does the author mean by saying that electricity is flexible?
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Lời giải:
Báo saiOn the other hand, we make use of electricity in thousands of ways. From the powerful voltages that drive our electric trains to the tiny current needed to work a simple calculator, and from the huge electric magnet in steel works that can lift 10 tons to the tiny electric magnet in a doorbell all are powered by electricity. An electric current can be made with equal ease to heat a huge mass of molten metal in a furnace, or to boil a jug for a cup of coffee... It is flexible, and so adaptable for any task for which it is wanted. (Mặt khác, chúng ta sử dụng điện theo hàng ngàn cách. Từ những hiệu điện thế mạnh thúc đẩy tàu điện của chúng ta đến dòng điện cực nhỏ cần thiết để hoạt động một chiếc máy tính đơn giản, và từ nam châm điện khổng lồ bằng thép có thể nâng được 10 tấn đến nam châm điện cực nhỏ trong chuông cửa, tất cả đều chạy bằng điện. Dòng điện có thể được tạo ra một cách dễ dàng để đốt nóng một khối lượng lớn kim loại nóng chảy trong lò, hoặc đun sôi một cái bình đựng một tách cà phê ... Nó rất linh hoạt và có thể thích ứng cho bất kỳ nhiệm vụ nào mà nó muốn.)
=> Điện được sử dụng trong tất cả các lĩnh vực, và thích hợp với rất nhiều cách dùng