Контрольная работа "Television" 9 класс

Контрольная работа по английскому языку в 9 классе

1. Read the text and complete it with the phrases (a - g) below.

a) This scans the screen.

b) Live television programmes show you what is happening as it happens.

c) Baird showed his set in 1926.

d) These pass into the TV set.

e) Scientists have been interested in the idea of television since the 1880s.

f) Now nearly every home has one.

g) These tiny flashes of colour build up the picture on your screen.

Television

Television is a way of sending sound and pictures through the air. (1) ___________

Although John Logie Baird was the first to show how television worked, his success was based

on work by many other scientists from all over the world. (2) __________ The first television

service opened in 1936 in Britain. Colour television began in the United States in 1956.

At first, all television was black and white. Few people owned television sets because they

were very expensive. (3) ______________________________________

Television works by changing light waves into electric signals. This happens inside the TV

camera. A picture of what is happening in front of the camera forms on a special behind the

lens. Behind the screen is an electron gun. (4) _____________________ It moves from left to

right to cover each part of the picture. Each part is turned into an electric signal which is made

stronger, then sent to the transmitter as radio waves. They are picked up by home TV antennas

and changed back into electric signals. (5)________

The TV screen is covered with tiny chemical dots. In a colour set, these are arranged in

groups of three: one red, one blue, one green. At the back there are other electron guns. These

fire a beam of electrons to scan the screen just as the camera gun does. As each electron hits

the screen, it lights up a dot. (6)___________ You do not see lines of coloured flashing lights,

because the electron gun moves too fast for the eye to follow. What you see is a picture of

what is happening in the television studio.

(7)___________ Most programmes are recorded on film or videotape and sent out later.

2. Read the text and mark each sentence after it "T" for true, "F" for false, "NS" for not

stated.

Stop talking rubbish about 3D printing

Pick up any technology magazine, and you’ll find sentimental articles about how the world is

going to be completely transformed by 3D printing – everyone from Wired to the Economist

has speculated on changes to society that 3D printing will bring. The ability to turn objects into

data – to copy physical things – has led many people to predict an attack of 3D piracy. It has

been written a lot about the criminal possibilities connected with the machines. Yesterday, the

founder of Makerbot came out to say his product will “fuel the next industrial revolution”.

Having talked to a bunch of manufacturing engineers, I’m not so sure. All the enthusiasm for

the “revolution” seems to come from journalist observers of the 3D printing scene, the

companies offering the “revolutionary technology”, and a handful of Lefty academics thrilled

by the idea of abolishing property. People actually involved in manufacturing are not so sure

that it’s magic. Let’s take a British example.

There was a huge internet furore a few months back when Games Workshop, a British toy

soldier manufacturer, felt it had been the world’s first victim of digital piracy, and issued a

takedown notice on a 3D printing pattern for a vehicle similar to one from its Warhammer

40,000 game. A huge wave of copying, a minefield of intellectual property issues, was

predicted.

In actual fact, very little of that has happened.

Patterns for model soldiers exist on file-sharing sites like the Pirate Bay. However, the

economics just don’t support pirating on that scale. Unlike, say, pirating music, where the act

of listening is free, printing out models costs money. A box of model soldiers goes for about

£20 online, about £25 in the shops – but the plastic to print them out at home currently costs

around £35, and the most common printer – the Makerbot – costs about £2,000. So an

epidemic of piracy seems unlikely. Printing is also a fairly exacting process – it takes time,

effort, and often you get a pile of goo at the bottom of your machine rather than the thing you

wanted. Widespread physical copying won’t happen, in the same way that photocopiers didn’t

lead to an epidemic of photocopying books.

The technology just isn’t there yet – even successful prints create models that look like they’ve

been left on a radiator for a few hours. And if it’s not good enough for model soldiers, it’s

certainly not good enough for things with complex moving parts. One engineer told me: “You

have to appreciate how expensive and how specialised most factory tooling is. You can run a

3D Printer for six months and never make the same item twice.”

He thought it would be 10 to 15 years before printers able to create factory-quality products

would appear, and those ones able to do in metal would probably never make it into the home.

He did, however, confidently predict being able to print out parts for his BMW on the factory

level ones in a few years’ time, but pointed out that those machines weren’t going to drop

below a million pounds a piece any time soon, and that even if they did, the materials to make

the parts at the right tolerance for a car were incredibly expensive to buy.

None of the current methods of home 3D printing – the thermal fusing of plastic filaments,

using UV light to cut polymer resin, depositing glue to bind resin powder, cutting and

laminating paper, or even using a laser beam to fuse metal particles – are even close to

reaching the standards a machine would require. It’s all very well to upload weapon parts to

the internet, but without the means to do metal you’ve printed yourself a cool accessory for

your Halloween gangster costume – and if you’re stupid enough to press the trigger, it’s more

likely to take your arm off than actually fire a bullet.

It strikes me that 3D printing is the microwave of manufacturing. If you look back at

newspapers from the 1970s, people predicted that microwaves would be the only device in a

kitchen, and that every dish would be microwaved. That never came to pass. Like microwaves,

3D printing will be important, but this isn’t the industrial revolution that techno-libertarians

would have you believe.

1) It seems 3D printing has been spoken and argued a lot about in the press.