Unit 4 energy
Exercise 1. a). The text you are going to read is headlined “Energy”. Guess what it can run about.
b).Think of 5-7 questions the answers to which you hope to find in the text.
c) In pairs, ask and answer these questions
Exercise 2. Mind the pronunciation of the following words:
measure ['meZq] to require [rI'kwaIq]
ability [q'bIlItI] quantity ['kwPntItI]
science ['saIqns] successive [sqk'sesIv]
weight [weIt] boundary ['baVnd(q)rI]
pulley ['pVlI] collision [kq'lIZ(q)n]
applied [q'plaId] pendulum ['pendjVlqm]
distance ['dIst(q)ns] to recognize ['rekqgnaIz]
to associate [q'sqVSIeIt] capacity [kq'pxsItI]
to exist [Ig'zIst] thermodynamics ["TE:mqVdaI'nxmIks]
to convert [kqn'vE:t] constraint [kqn'streInt]
Exercise 2. Guess the meaning of the following international words:
Energy, kinetic, potential, electrical, chemical, constant, magnetic, mass, total, principle, term, idea, configuration, natural, transformation, process, elastic.
Exercise 3. Choose Russian-English equivalents in the box below.
electric current |
ядерный |
to remain constant |
в покое |
thermal energy |
способность |
nuclear |
независимо от, не принимая во внимание |
at rest |
постепенно |
to contain |
столкновение |
within the constraint |
тепловая энергия |
regardless of |
рассеивать |
collision |
электрический ток |
to dissipate |
в рамках действия |
progressively |
оставаться постоянной |
capacity |
содержать, вмещать |
Exercise 4. The words in A are mentioned in the text “Energy”. Find their definitions in B and translate these words into Russian.
A |
B |
measure |
weighted rod hung from a fixed point so that it swings freely |
energy |
pressure or influence exerted at a point, tending to cause movement |
elastic |
to keep from change, loss or destruction |
pendulum |
high temperature |
friction |
unit, standard or system used in stating size, quantity, or degree |
to conserve |
force of attraction between any two objects, esp. that force that attracts objects towards the centre of the earth |
heat |
the rubbing of one thing against another, esp. when it wastes energy |
force |
power of, capacity for doing work |
gravity |
to change from one form into another |
to convert |
having the tendency to go back to the normal or previous size or shape after being pulled or pressed |
Exercise 5. Find the derivatives of the following words in the text. Pay attention to the suffixes used to form them.
to regard |
to discover |
to conserve |
to vary |
to evaluate |
wide |
conclusive |
to describe |
careful |
to collide |
nature |
relative |
able |
to develop |
to state |
to differ |
Exercise 6. Match nouns and verbs to form collocations. Use each word once only. Consult the text if necessary.
to go back to |
transformations |
to apply |
heat |
to result from |
energy |
to include |
motion |
to lose |
successive evaluations |
to slow down |
natural phenomena |
to generate |
the 18th century |
to create |
a mechanism |
to hold for |
a force |
to go on between |
configuration |
Exercise 7. There are some words given in italics in the text “Energy”. Choose their synonyms from the box below. The forms of the words in the text may differ from those in the box.
ability |
despite |
important |
stable |
sequential |
to raise |
result |
limit |
to change |
immobility |
various |
movement |
Read the text and fulfill the tasks given in Comprehension check.
ENERGY
The term energy was not applied as a measure of the ability to do work until rather late in the development of the science of mechanics. The idea of energy goes back at least to Galileo in the 17th century.
He recognized that, when a weight is lifted with a pulley system, the applied force multiplied by the distance through which that force must be applied (a product called, by definition, the work) remains constant even though either factor may vary.
Energy is the capacity for doing work. It may exist in many forms. These different forms include potential, kinetic, thermal, electrical, chemical, nuclear, or other various forms. All forms of energy are associated with motion. For example, any given body has kinetic energy if it is in motion. A tensioned device such as a bow or spring, though at rest, has the potential for creating motion; it contains potential energy because of its configuration. Similarly, nuclear energy is potential energy because it results from the configuration of subatomic particles in the nucleus of an atom.
Energy can be converted from one form to another within the constraint of the conservation law. The law of conservation of energy holds for all natural phenomena and requires that the total energy does not change in all changes that occur in nature. The conservation of energy is not a description of any process going on in nature, but rather it is a statement that the quantity called energy remains constant regardless of when it is evaluated or what processes--possibly including transformations of energy from one form into another—go on between successive evaluations.
The law of conservation of energy is applied not only to nature as a whole but to closed or isolated systems within nature as well. Thus, if the boundaries of a system can be defined in such a way that no energy is either added to or removed from the system, then energy must be conserved within that system regardless of the details of the processes going on inside the system boundaries.
The first kind of energy to be recognized was kinetic energy, or energy of motion. In certain particle collisions, called elastic, the sum of the kinetic energy of the particles before collision is equal to the sum of the kinetic energy of the particles after collision. The notion of energy was progressively widened to include other forms. The kinetic energy lost by a body slowing down as it travels upward against the force of gravity was regarded as being converted into potential energy, or stored energy, which in turn is converted back into kinetic energy as the body speeds up during its return to Earth. So the sum of the kinetic and the potential energy of, say, a satellite or a freely swinging pendulum is constant or nearly so. Friction, however, slows down the most carefully constructed mechanisms, thereby dissipating their energy gradually. During the 1840s it was conclusively shown that the notion of energy could be extended to include the heat that friction generates. The truly conserved quantity is the sum of kinetic, potential, and thermal energy. This version of the conservation-of-energy principle, expressed in its most general form, is the first law of thermodynamics. The conception of energy continued to expand to include energy of an electric current, energy stored in an electric or a magnetic field, and energy in fuels and other chemicals.
With the advent of relativity physics (1905), mass was first recognized as equivalent to energy. The total energy of a system of high-speed particles includes not only their rest mass but also the very significant increase in their mass as a consequence of their high speed. After the discovery of relativity, the energy-conservation principle has alternatively been named the conservation of mass-energy or the conservation of total energy.
Notes to the text
The first kind of energy to be recognized …первым видом энергии, который смогли распознать (выделить), ….
The kinetic energy … was regarded as being converted …кинетическая энергия, как считали, превращается в …
Comprehension check
Exercise 1. Choose the best ending a, b, or c.
The idea of energy dates back to
Newton.
Galileo.
ancient Greek scientists.
Energy is
the ability to do work.
is equal to the product of the applied force and the distance through which that force must be applied.
equals mass times one-half of the velocity squared.
Energy may exist in
two main forms, i.e. kinetic and potential.
only if a body moves.
different forms that are associated with motion.
Energy
never changes without losses.
can be transformed from one form to another in accordance with the conservation law.
of a falling body doesn’t remain constant.
The law of conservation of energy
states that the total energy does not change in manifold changes that nature undergoes.
is applied only to natural phenomena.
holds only for bodies at rest.
The first form of energy that was recognized by scientists was
nuclear energy.
potential energy.
energy of motion.
The kinetic energy lost by a body when it travels upward is converted into
thermal energy.
potential energy.
chemical energy.
Mass energy was first recognized
when nuclear physics arose.
after the discovery of relativity.
with the advent of atomic physics.
Exercise 2. Find answers to the following questions.
What is energy?
When was the term energy used as a measure of the ability to do work?
What did Galileo think?
What forms of energy do you know?
Can energy be converted?
What does the law of conservation of energy state?
Where is the law of conservation of energy applied?
What was the first type of energy to be recognized?
When does kinetic energy convert into potential energy?
When was heat recognized as a form of energy?
What is the truly conserved quantity/
What is electrical energy?
What happened when relativity physics arose?
Exercise 3. Put the jumbled sentences in the logical order to sum up the contents of the text.
The law of conservation of energy is applied to nature as a whole and to closed or isolated systems within nature.
Energy is the capacity for doing work.
The notion of energy constantly widened to include more and more forms of energy.
All these forms of energy are connected with motion.
The idea of energy originated in the 17th century.
The energy-conservation principle changed its name to the mass-energy conservation principle.
The first kind of energy that was recognized was kinetic energy.
The term energy was used as a measure of the ability to do work rather late.
There are many forms of energy: potential, kinetic, thermal, electrical, chemical and others.
When relativity physics emerged, mass was regarded as equivalent to energy.
Energy can be converted from one form into another.
The law of conservation of energy requires that the total amount of energy remain constant.
Grammar exercises
Modal verbs: can/could, be able to, may/might. (Meanings expressed by these modal verbs: ability, absence of ability, request, asking for permission, giving permission, refusing permission, reproach).
Exercise 1. Choose the correct alternative.
May/Can I record our interview on tape? – Yes, of course you may/can.
People heard warnings about the flood, and they could/were able to move out in time.
Peter can/may phone in the evening. If he does, ask him to phone later.
As soon as I opened the door, I could/might smell gas.
Confidential documents may not/cannot be photocopied without prior approval.
I thought I was going to miss the plane but I could/was able to get to the airport on time.
James broke his leg last summer, so he couldn’t/wasn’t able to play tennis.
My appointment was cancelled at the last moment, so I could/was able to go to the fitness centre with my friends.
Catherine couldn’t/wasn’t able to speak any Dutch when they moved to the Netherlands last year.
I had no key so I couldn’t/wasn’t able to lock the door.
When I arrived yesterday everyone was asleep. Fortunately I could/was able to wake my brother and he let me in.
Although it was dark, Robin could/was able to find his way through the forest.
We could/were able to finish the football match before it started snowing too heavily.
Do you want a game? – Sorry, I can’t/am not able to play chess.
Look at me, I can’t/am able to ride my bike without any help.
When the fire officers arrived they could/were able to put out the flames in a couple of minutes.
I knew John had been smoking. I could/was able to smell the cigarettes when I came into the room.
He could/was able to untie the ropes without the guards noticing.
She looked all over the house, but couldn’t/wasn’t able to find her keys anywhere.
I was very busy at work, but I could/was able to have a couple of days off last week.
Exercise 2. Fill in the blanks using can/could, be able to, may/might.
In two years you will … speak two foreign languages.
The information … be true! I don’t believe you.
Last year we … visit Canada.
… you help me carry these heavy bags?
She is rather old now and … to read without spectacles.
She … dance well.
Our secretary … to type 100 words a minute.
You … at least call her parents.
You enter this territory. It is dangerous.
I … to meet you at the station yesterday. I was very busy.
… I ask you a question, sir?
You … not smoke in the corridors.
You … do it yourself! It is an easy exercise.
… I get down to discussion right now, madam? – Yes, you … .
Though I … swim well some years ago, once I … to help a drowning man.
The stadium was full of fans, but we … to get tickets for this match.
I … to pass my driving test after I have had a few lessons.
… I come again? – Yes, you … come at any time you like.
She … speak three languages, but she … write any of them when she was younger.
Modal verbs: must, have to, be to, ought to, should. (Meanings expressed by these modal verbs: necessity, duty, obligation, lack of necessity, prohibition, advice, planned action).
Exercise 1. Choose the correct alternative.
You mustn’t/don’t have to leave your things unattended.
All the payments must/should be made before the goods are delivered.
The meeting is to/has to start at 10 sharp tomorrow.
As the payment was not made in time, they should/had to break the order.
You must/have to take a taxi if you want to catch the next train.
I didn’t have to/ mustn’t go to the bank yesterday as I had enough money on me.
Students shouldn’t/mustn’t talk at the lectures, they have to/must listen to attentively.
Since the new boss took us over, we had to/were to change our methods of work.
You’ve got plenty of time. You don’t have to/mustn’t hurry.
This book is very valuable. You must/have to handle it carefully.
When I was at school we had to/should wear a uniform. Everybody liked it.
I like Saturdays because I don’t have to/am not to be in a hurry in the morning.
If you feel tired, you should/have to go to bed earlier.
You mustn’t/don’t have to invite guests to your hotel rooms.
Last night Jack suddenly became ill. We had to/must call the doctor.
Your friend is always coughing, he must/has to stop smoking.
I don’t have to/mustn’t wear a suit to work, but I usually do.
You can tell Tom what I said but he mustn’t/doesn’t have to tell anybody else.
Exercise 2. Fill in the blanks using have to, must, be to, should, ought to.
You … bite your nails.
Mary, you will … take our dog for a walk.
He … to stay at home yesterday because of high temperature.
You … tell them the truth.
We … to finish the reconstruction according to the signed contract.
You … lock the door at night.
They … to meet last Friday to discuss important questions.
Everyone … obey the law.
The bus didn’t come on time, so we … to wait long at the bus stop.
You … tell anybody about our meeting. Let’s keep it secret.
You … do it at once, otherwise you will let me down.
One … look both ways before crossing the street.
You … be late. You … to come at 5 o’clock. They will be waiting for you there. – I … to take a taxi to be on time.
We … do our homework carefully not to make any mistakes.
You … come. There is nothing to do.
I don’t think people … get married until they are 21.
Modal verbs can, can’t, must, may/might. (Meanings expressed by these modal verbs: possibility, assumption, doubt, surprise).
Exercise 1. Choose the correct alternative.
Do you think the situation may/must change?
Can/May he be working out the report?
Nothing is so bad but it might/must have been worse.
How did they manage to do well last month? – They must/can have increased productivity.
He may/can’t have made such a mistake in calculations!
Ted didn’t answer the phone so he must/can’t have gone on holiday.
Do you think they are all right? They must/can have had an accident or something.
What a terrible risk you took – you may/must have been killed!
I am waiting for Alice but she might/can’t have forgotten about the meeting.
He did everything wrong. He must/can’t have misunderstood you.
It is wet outside. It must/may have been raining all the night.
Exercise 2. Fill in the blanks using, must, may/might, can’t.
You … be very tired after such a long flight.
We … go climbing in the Alps next summer.
He … not have arrived yet.
You … have told me about that accident earlier!
She … be talking seriously!
… they have been negotiating the contract for two hours?
I am not sure at all but Tom … know about it.
Oh no! I cannot find my passport anywhere. - I think it … be in your briefcase or you … have left it at work.
His face is red. He … be cold.
Wait a minute, the rain … stop soon.
… Sally have spent all her money?
They … be walking in the park now.
Follow–up activities
Exercise 1. Find in the text “Energy” and read sentences in which
the time when the tem energy appeared is indicated;
the definition of energy is given;
the law of energy is stated;
forms of energy are enumerated;
possible fields of application of the law of energy conservation are named.
Exercise 2. Use the following key words and word combinations to express the main idea of each paragraph.
The idea of energy, to go back to, Galileo.
A product, the applied force, the distance, to remain constant, either factor, to vary.
Energy, capacity, to do work.
To exist, forms of energy.
Energy, to convert, forms.
The law of conservation, to hold, natural phenomena.
The law of conservation, to state, total energy, to change.
The law of conservation, to apply, nature, closed systems.
The notion of energy, to widen, to include, different forms of energy.
The advent, relativity physics, the energy-conservation principle, to name, mass-energy.
Exercise 3. Choose the key sentences from the text “Energy”, write them down omitting less important information. Now work in pairs (or in groups). Ask your groupmate(s) to translate your Russian versions of the key sentences into English. Swap the roles.
Exercise 4. You are a guest speaker at some conferences. You were asked to deliver a report about energy. Use the information from the text and add some more to speak on the problem suggested.
Exercise 5. Watch the video film “Kinetic Energy” and fulfill the tasks to follow.
Task 1. Combine two parts of sentences.
force |
is the amount of work done when one Newton of force is applied through a distance of one metre. |
work |
is measured in newtons. |
force |
is measured in joules. |
energy |
equals mass times acceleration. |
one joule |
is the energy of movement |
kinetic energy |
is the ability to do work. |
Task. 2. Answer the following questions.
What is necessary to make stationary things move?
When is work done?
Why doesn’t the first billiard ball move
Why does this ball start moving?
Why can the second ball make the first one move?
Where did physicists borrow the English word energy?
What does this word mean in Greek?
Why does the moving ball have energy?
Is work possible without energy?
In what units is energy measured?
Where does the word kinetic come from? What does this word mean?
Task 3. Put the jumbled sentences in the logical order to sum up the contents of the video film.
The first billiard ball doesn’t move because no force acts on it.
The English word energy comes from Greek.
This energy was transferred to the cue which in turn transferred the energy to the billiard ball by making it move.
Stationary things do not move.
The second billiard ball makes the first one move as it has movement.
If an object has both mass and speed, it has the ability to do work, i.e. to get other things to move.
The moving ball had some energy and the origin of this energy was the billiard player whose arm had work in it or energy because of its movement.
Physicists decided to call the energy of movement kinetic energy.
Force is necessary to make them move.
When a force moves an object through some distance, work is done.
Exercise 6. Watch the video film “Potential Energy” and fulfill the tasks to follow.
Task 1. Agree or disagree with the following statements. Give arguments in support of your ideas.
Moving things have the ability to do work but they can’t apply a force through a distance.
Energy is the capacity for doing work.
Work is measured in joules and energy – in newtons.
Kinetic energy is the energy of position.
Only moving things have energy.
Stationary objects possess potential energy.
Potential energy can transform into kinetic energy when a stationary object starts moving.
kinetic energy can change into potential energy when a moving object comes to a complete stop.
After climbing up to the top of the cliff the giant has lost all his energy.
Exercise 2. Arrange the jumbled sentences into the logical order to sum up the contents of the video film.
In turn kinetic energy can transform into potential energy when an object stops moving.
But they have the energy of position or what physicists call potential energy.
The rock on the edge of the cliff has potential energy and no kinetic energy.
Moving objects have the ability to do work.
Stationary objects can’t have any kinetic energy and they can’t do any work on you.
Both work and energy are measured in joules.
Not only moving objects have energy.
Nevertheless this potential energy can transform into kinetic energy due to the slightest puff of the wind.
Thus energy is never lost, one form of it can be transformed into another.
The energy of movement is called kinetic energy.