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Unit 10 wireless electricity lead - in activity

Task 1. Short discussion.

  1. Imagine what will happen if the supply of energy or electricity to our houses stops so what will you do, how will our life change?

  2. Do you know who invented electricity? What is the name of this scientist and what do you know about him and his work?

  3. What devices do you know which work without wires?

Task 2. Look at the pictures showing different wireless devices. What are their main advantages and disadvantages?

A

B

C

D

E

READING

Task 3. Read the following words and find their Ukrainian equivalents. Try to explain their meanings:

conventional, transference, wastage, display, widespread, to exist, efficiency, a coil, advantage, to tune, frequency, techniques, electricity, modern, wireless, transmitter.

Task 4. Read and translate the text:

Wireless electricity

Electricity is today a necessity of modern life. It is difficult to imagine passing a day without electricity. The conventional use of electricity is made possible through the use of wires. However researchers in MIT have devised means of providing electricity without any wires.

These researchers coined the term witricity; which is basically a portmanteau for wireless electricity. This principle of wireless electricity works on the principle of using coupled resonant objects for the transference of electricity to objects without the use of any wires. A witricity system consists of a witricity transmitter and another device called the receiver.

The receiver works on the same principle as radio receivers where the device has to be in the range of the transmitter. It is with the help of resonant magnetic fields that witricity produces electricity, while reducing the wastage of power.

While the idea may sound futuristic, it isn't particularly new. Nicola Tesla proposed theories of wireless power transmission in the late 1800s and early 1900s. One of his more spectacular displays involved remotely powering lights in the ground at his Colorado Springs experiment station.

Tesla's work was impressive, but it didn't immediately lead to widespread, practical methods for wireless power transmission. Since then, researchers have developed several techniques for moving electricity over long distances without wires. Some exist only as theories or prototypes, but others are already in use.

So far the MIT researchers have been able to power a 60 watt light bulb from a power source that is located about seven feet away, while providing forty percent efficiency. This was made possible using two copper coils that were twenty inches in diameter which were designed so that they resonated together in the MHz range. One of these coils were connected to a power source while the other, to a bulb. With this witricity setup, the bulb got powered even when the coils were not in sight.

If you have an electric toothbrush, for example, you probably take advantage of one method every day.

The wireless transmission of energy is common in much of the world. Radio waves are energy, and people use them to send and receive cell phone, TV, radio and WiFi signals every day. The radio waves spread in all directions until they reach antennae that are tuned to the right frequency. A similar method for transferring electrical power would be both inefficient and dangerous.