Find the words in the text that mean the following. 1. a line or plane that is at right angles to another line or plane.

1. a line or plane that is at right angles to another line or plane.

2. describing two or more geometric figures that differ only at location in space.

3. the length of a closed curve.

4. a measure of extent in a three-dimensional space.

5. a solid figure formed from two congruent polygons with their corresponding sides parallel (the bases) and the parallelogram (lateralfaces) formed by joining the corresponding vertices of the polygons.

 

Now complete the sentences with the appropriate form of the words from exercise 6.

1. For solid figures bounded by curved surfaces ___ is found by integration.

2. Could you find the ___ of this ellipse?

3. These lines are ___ to each other.

4. It is a well-known fact that two plane figures can be ___ without being identical,

5. A right ___ is one in which the lateral edges are at right angles to the bases

 

Which of the following statements are true or false?

1. A solid is a four-dimensionalfigure.

2.A pyramidis a solid figure (a polyhedron) formed by a polygon (the base) and a number of triangles (lateral faces) with a common vertex that is coplanarwith the base.

3. A cone is a solid figure formed by a closed plane curve on a plane ( thebase) and all the lines joining points of the base to a fixed point (the vertex) not in the plane of the base.

4. The altitude (h) of a pyramid isn't the perpendicular distance from the base to the vertex.

Answer the following questions.

1. How many congruent polygons form a prism?

2. How many triangular bases does a triangular prism have?

3. What are the bases of pentagonal and hexagonal prisms?

4. At what angles to the bases are the lateral edges of a right prism?

5. A regular prism is a prism whose bases are regular polygons, isn’t it?

6. What curve plays the role of the directrix of the cone?

7. What are generators or elements of a cone?

8. Cones are named according to the base, aren’t they?

9. What cone has its axis perpendicular to its base?

10. What is the altitude of a cone?

Describe three types of prisms: a triangular prism, a quadrangular prism, a pentagonal prism.

Speak about different solids (in 8-10 sentences).

TEXT 12B  

What are telecommunications?

Learn the following active words and word combinations.

telecommunications – телекоммуникации

to transmit – передавать

digital TV– цифровое телевидение

satellite – спутник

teleworking – дистанционная работа

call centre –  колл-центр (телефонный информационный центр)

online chat – онлайн чат

to broadcast – вещать, транслировать

analogue signal – аналоговый сигнал

interactive service – интерактивная услуга

pay multimedia – платные мультимедиа

terrestrial TV – эфирное телевидение

set-top box – телеприставкаж

aerial – антенна

wireless connectivity– беспроводная связь

wearable computers – нательный компьютер

 

Give the Russian equivalents for the following words and expressions from the text.

for the purpose of, via modem, outside the workplace, teletext pages, to be predicted, to browse, the Web, check one’s email, to navigate, to activate, by voice, aerial, on a pay-per-view basis.

Find the answers to these questions by quickly reading the text.

What devices are used to transmit information?

What is the basic difference between digital TV and traditional TV?

Read and translate the text.

Telecommunications

Telecommunications refers to the transmission of signals over a distance for the purpose of communication. Information is transmitted by devices such as the telephone, radio, television, satellite, or computer networks. Examples could be two people speaking on their mobile phone, a sales department sending a fax to a client, or even someone reading the teletext pages on TV. But in the modern world, telecommunications mainly means transferring information across the Internet, via modem, phone lines or wireless networks.

Because of telecommunications, people can now work at home and communicate with their office by computer and telephone. This is called teleworking. It has been predicted that about one third of all work could eventually be performed outside the workplace. In call centres, assistance or support is given to customers using the telephone, email or online chats. They are also used for telemarketing, the process of selling goods and services over the phone.

Digital TV and radio

In recent years, TV and radio broadcasting has been revolutionized by developments in satellite and digital transmission. Digital TV is a way of transmitting pictures by means of digital signals, in contrast to the analogue signals used by traditional TV. Digital TV offers interactive services and pay multimedia – that is, it can transmit movies and shows to TV sets or PCs on a pay-per-view basis. It is also widescreen, meaning programmes are broadcast in a native 16:9 format instead of the old 4:3 format. Digital TV provides a better quality of picture and sound and allows broadcasters to deliver more channels.

Digital Terrestrial TV is received via a set-top box, a device that decodes the signal received through the aerial. New technologies are being devised to allow you to watch TV on your mobile. For example, DMB (Digital Multimedia Broadcasting) and DVB-H (Digital Video Broadcast-Handheld) can send multimedia (radio, TV and data) to mobile devices.

Mobile communications

Thanks to wireless connectivity, mobile phones and BlackBerrys now let you check your email, browse the Web and connect with home or company intranets, all without wires.

The use of GPS in cars and PDAs is widespread, so you can easily navigate in a foreign city or find the nearest petrol station. In the next few years, GPS chips will be incorporated into most mobile phones.

Another trend is wearable computers. Can you imagine wearing a PC on your belt and getting email on your sunglasses? Some devices are equipped with a wireless modem, a keypad and a small screen; others are activated by voice. The users of wearable technology are sometimes even called cyborgs! The term was invented by Manfred Clynes and Nathan Kline in 1960 to describe cybernetic organisms – being.