Английский - 2курс_3семестр_physics

We use be going to:

for plans and intentions we have about the near future.

Bob is going to drive to Manchester tomorrow morning.

when there is evidence that something is going to happen in the near future.

Look at that tree. It is going to fall down.

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EXERCISES

1. In pairs, ask and answer questions using the prompts below, as in the example.

SA: Will you have a party on your birthday this year?

SB: Yes, I will. / No, I won’t.

1)have a party on your birthday this year?

2)go to university when you finish school?

3)travel abroad if you have enough money?

4)go out with your friends at the weekend?

5)watch TV this evening?

6)study hard for next term‘s exams?

7)learn how to drive next summer?

2. Answer the following questions about yourself using I think/I hope/I expect

I’ll … or I’m sure/I’m afraid I’ll …, as in the example.

1)Where will you be at 5 o‘clock tomorrow afternoon?

I expect I’ll be at home.

2)Where will you go at the weekend?

3)Where will you spend your holidays?

4)What will you do if you fail your exams?

5)When will you buy your own car?

6)Who will you ask for help if you are in trouble?

3. Put the verbs in brackets into the present indefinite or the future indefinite.

1)They …will/‘ll go… (go) to school when they … (be) five years old.

2)I … (call) you before I … (leave) for Paris.

3)He … (write) a letter to her every day while he … (be) at college.

4)We … (do) our homework when we … (get) home.

5)John … (fix) the tap as soon as he … (come) back from work.

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6)When … (you/pack) your suitcase?

7)I … (not/do) anything until you … (be) ready.

8)When … (you/phone) me?

9)I promise I … (buy) you a present when I … (return) from my holiday.

10)When she … (pass) her driving test, she … (buy) a car.

4. Fill in the gaps with shall, will or the correct form of be going to.

1)- The shops are closed tomorrow.

-I …will…buy bread and milk today then.

2)- … we tell Mr Peck about the accident?

-That‘s a good idea. Maybe he can help.

3)- It‘s too dark in here to read.

-Is it? I … turn on the light.

4)- Please come and see us.

-We … visit you soon, that‘s a promise.

5)- … I wear a jumper or a coat?

-It‘s cold. Take your coat.

6)- Can we go out to play, Mum?

-No, we … have dinner now.

5. Correct the mistakes.

1)Will I take the children to the playground for you?

2)I‘ll call you when I will finish work.

3)Will you to clean the carpet, please?

4)The film is starting at 8 o‘clock.

5)Wait here until he will come.

6)The Queen won‘t not attend the parade tomorrow.

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UNIT 6

Newton‟s First Law

Read the text and express its main idea.

Isaac Newton stated three laws of motion.

The first law deals with forces and changes in velocity. For just a moment, let us imagine that you can apply only one force to an object. That is, you could choose push the object to the right or you could choose to push it to the left, but not to the left and right

at the same time, and also not up and to the right at the same time, and so on. Under these conditions the first law says that if an object is not pushed or

pulled upon, its velocity will naturally remain constant. This means that if an object is moving along, untouched by a force of any kind, it will continue to move along in a perfectly straight line at a constant speed.

This also means that if an object is standing still and is not contacted by any forces, it will continue to remain motionless. Actually, a motionless object is just a special case of an object that is maintaining constant velocity. Its velocity is constantly 0 m/s.

Now, what about if there is more than one force on the object? You really can push an object, say, to the left and down at the same time, so, what happens then?

Under these conditions we must realize that a group of forces on an object adds up so that all the forces appear to the object as one force. This one force that is the sum of all the forces is called the net force. The word net in this context means total. It is this net force that may change the velocity of the object. Let us look at some examples.

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Imagine that two forces act at the same time on an object. One is a very strong force to the left, and the other is a weaker force to the right. These two forces add up to one net force. Since the force to the left is stronger, the net force is to the left. This net force to the left will cause the velocity of the object to change. The object experiences this one net force as if this was the only force pushing it, although, actually, there are two separate forces present. Next let us see what happens when two forces act, but they are equal in strength.

Imagine that two forces, one up and one down, push on an object, and imagine that the two forces are the same size. These two forces add up as before, but this time one of them does not overpower the other. They cancel each other out. So, in this example the net force is zero. It is as though no forces were really acting on the object. Under these conditions the velocity of the object would not change. If it was moving in a straight line at constant speed before the two forces were applied, then it would continue to move in a straight line at constant speed after these two equal and opposite forces were applied. If it was standing still before the application of these forces, it would continue to stand still afterwards.

The net force is the total force. It could be the sum of two forces or more than two forces. If only one force acts upon an object, then this one force would be the net force. If the net force on an object is zero, then the object experiences no velocity change. If the net force on an object is not zero, then the object will show a change in velocity.

Lastly, this net force must be external to the object. The net force can not come from the object itself. You could not, for example, put on ice skates, stand on a frozen pond, push on your back by reaching around with your arms, and expect to get going. Although if someone else came up from behind and gave you a shove, then your velocity would change.

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But skaters do get going all by themselves, so, how does that happen? Well, that answer is in Newton's third law of motion.

Newton's first law of motion contains the same information as Galileo's explanation of inertia.

Put 10 questions to the text and let other students answer them.

Discussion Questions

A Newton said that objects continue moving if no forces are acting on them, but his predecessor Aristotle said that a force was necessary to keep an object moving. Why does Aristotle‘s theory seem more plausible, even though we now believe it to be wrong? What insight was Aristotle missing about the reason why things seem to slow down naturally? Give an example.

B In the figure what would have to be true about the saxophone‘s initial motion if the forces shown were to result in continued one-dimensional motion of its center of mass?

C This figure requires an ever further generalization of the preceding discussion. After studying the forces, what does your physical intuition tell you will happen? Can you state in words how to generalize the conditions for one-dimensional motion to include situations like this one?

State the Newton’s First Law.

What questions would you like to ask Isaac Newton?

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GRAMMAR

The Passive Voice

to be + past participle (pp)

The passive verb forms are:

We form questions by putting the verb to be before the subject. Is your car being serviced?

We form negations with the word not.

The furniture has not been delivered yet.

We form the passive of infinitives like this: to be + past participle

He wants to be told the truth.

We form the passive of modal verbs like this:

modal verb + be + past participle

The roof of the house must be repaired.

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We use the passive when we want to show that the action of the verb is

more important than the person who carries out the action.

The missing climber was found yesterday. (The action (was found) is more

important than the person who found the climber.)

The agent (the person who carries out the action) is introduced with the preposition by and is mentioned only when the identity of

the agent is important or needs to be stated.

Australia was discovered by Captain Cook. (by Captain Cook – The identity of the agent is important.)

The agent is not mentioned when: a) it is known.

Jim‘s car was stolen last night. (We don‘t know who stole Jim‘s car.) b) it is unimportant.

Olive oil is produced in Mediterranean countries. (The agent is unimportant.) c) it is obvious from the context.

The bank robbers are being chased. (It is obvious that the police are chasing them.)

EXERCISES

1. Rewrite the sentences in the passive.

1)They will not deliver the new sofa on Friday.

The new sofa will not be delivered on Friday.

2)You can use this saucepan for cooking spaghetti.

3)I have to finish my homework tonight.

4)You must tidy your bedroom.

5)You ought to put these clothes away.

6)The boss gave the secretary some letters to type.

7)We should eat this cake immediately.

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8)Sally sent Peter a birthday card.

9)You must take the dog for a walk.

10)The cat is not chasing the mouse.

11)Do they produce oil in Spain?

12)Did a dog bite him?

13)Edward has not recorded a new song.

2. Rewrite the sentences in the passive.

1)The pop star sang the song.

The song was sung by the pop star.

2)The chef hasn‘t made dinner.

3)An explorer has found a dinosaur egg.

4)Mrs Gates will look after the baby.

5)They won‘t take him home after the party.

6)Someone left the front door open.

7)Jenny didn‘t break the window.

8)Someone is using the computer.

9)His brother taught him to drive.

10)Many people speak English.

11)The doctor had already told him to go on a diet.

12)The author is writing a new book.

3. Write questions in the passive to which the words in bold are the answers,

as in the examples.

1)Captain Cook discovered Australia.

Who was Australia discovered by?

2)A dog was chasing Paul.

3)Simon is going to organize the party.

4)A bee stung him.

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5)Fiona cooked this delicious turkey.

6)An international company publishes these books.

7)A bomb killed the soldier.

4. Rewrite the following passage in the passive.

Somebody sent me a bunch of flowers. The man from the flower shop delivered them to my house. He told me that they were a present. A young man had ordered them. He had put no card in the flowers. I still don‘t know who sent them.

5. Correct the mistakes.

1)The dishes has been washed.

2)The letters are being opened every morning in the office.

3)Your homework must finished by Monday.

4)The woman seen taking the children to school.

5)Mike has been tell about the new job.

6)The cars stole from the car park.

7)The house is been decorated recently.

8)The centre will visit by the King next month.

6. Fill in the active or passive form of the verbs in brackets.

Mrs Wilson is a rich young lady. She 1) …lives… (live) in a big house on the outskirts of the city with her husband and her two dogs. Every day, Mrs Wilson

2) … (take) into the city centre. Her car 3) … (drive) by her chauffeur. She then

4) … (go) shopping in her favourite shops. Her bags 5) … (carry) by the chauffeur. Mrs Wilson 6) … (buy) lots of things every week. She 7) … (need) lots of clothes because she goes to lots of parties. In fact, this week she 8) …

(invite) to a big birthday party which 9) … (hold) in a large mansion in the country. All of her friends will be there, so Mrs Wilson 10) … (look forward) to it very much.

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