GIAO TRINH PRO ENGLISH P2

[ C ] SPECIALIZED in physics the amount of matter in any solid object or in any volume of liquid or gas The acceleration of a body equals the force exerted on it divided by its mass.. G

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Mass: /mæs /

• mass /mæs/ adjective [ before noun ]

having an effect on or involving a large number of people or forming a large amount

weapons of mass destruction

a mass murderer

• mass /mæs/ noun LARGE AMOUNT

1 [ S ] a large amount of something that has no particular shape or

arrangement

The explosion reduced the church to a mass of rubble

The forest is a mass of colour in autumn

• mass /mæs/ noun PHYSICS

7 [ C ] SPECIALIZED (in physics) the amount of matter in any solid object or in any volume of liquid or gas

The acceleration of a body equals the force exerted on it divided by its mass

• mass /mæs/ verb [ I ]

to come together in large numbers

Thousands of troops have massed along the border in preparation for an

invasion

• measure /ˈmeʒ.ə r / /-ɚ/ noun METHOD

[ C usually plural ] a way of achieving something, or a method for dealing with a situation

What further measures can we take to avoid terrorism?

• amount /əˈmaʊnt/ noun [ C ] :

a collection or mass especially of something which cannot be counted

They didn't deliver the right amount of sand

• matter /ˈmæt.ə r / /ˈmæt ̬.ɚ/ noun SUBSTANCE

[ U ] physical substance in the universe

Some scientists believe that there is about ten times as much matter in the universe as astronomers have observed

Mass: /mæs /

• object /ˈɒb.dʒɪkt/ /ˈɑːb-/ noun THING

[ C ] a thing that you can see or touch but that is not usually a

living animal, plant or person

a solid/material/physical object

• molecule /ˈmɒl.ɪ.kjuːl/ /ˈmɑː.lɪ-/ noun [ C ]

The simplest unit of a chemical substance, usually a group of two or more atoms

• atom /ˈæt.əm/ /ˈæt ̬-/ noun [ C ] : nguyên tử

the smallest unit of any chemical element, consisting of a

positive nucleus surrounded by negative electrons Atoms can combine to form a molecule

A molecule of carbon dioxide (CO 2 ) has one carbon atom and two oxygen atoms

Mass: /mæs /

• proton /ˈprəʊ.tɒn/ /ˈproʊ.t ̬ɑːn/ noun [ C ]

a type of elementary particle (= very small piece of matter) which has a positive electrical charge and is found in the

nucleus of all atoms

• neutron /ˈnjuː.trɒn/ /ˈnuː.trɑːn/ noun [ C ]

a part of an atom that has no electrical

• electron /ɪˈlek.trɒn/ /-trɑːn/ noun [ C ]

an extremely small piece of matter with a negative electrical

• bark /bɑːk/ /bɑːrk/ noun TREE

[ U ] the hard outer covering of a tree

Mass: /mæs /

• iron /aɪən/ /aɪrn/ noun METAL

[ U ] a common silver-coloured metal element which is

magnetic It is strong, used in making steel and found in very small amounts, in a chemically combined form, in blood

Iron rusts easily

• fundamental /ˌfʌn.dəˈmen.t ə l/ /-t ̬ ə l/ adjective

forming the base, from which everything else develops; more important than anything else

We need to make fundamental changes to the way in which we

treat our environment

Mass: /mæs /

• block /blɒk/ /blɑːk/ noun BUILDING

[ C ] a large, usually tall building divided into

separate parts for use as offices or homes by several different organizations or people

an office block

Mass: /mæs /

• nature /ˈneɪ.tʃə r / /-tʃɚ/ noun LIFE

Nature means all the things in the world which exist naturally

and were not created by people

He's fascinated by wildlife and anything to do with nature

• constitute /ˈkɒn.stɪ.tjuːt/ verb BE CONSIDERED AS

[ L only + noun not continuous ] FORMAL to be or be considered

as something

This latest defeat constitutes a major setback for the

government

Mass: /mæs /

• The Mass of an object is a measure of the amount

of matter an object contains It is useful to consider that all objects (matter) are made of molecules and atoms, which in turn are made up of protons

neutrons and electrons The Protons, electrons and neutrons that make up tree bark are no different

than those that make up water, air or iron These fundamental building blocks of nature is what

constitutes the mass of an object

Gravity

• gravity /ˈgræv.ɪ.ti/ /-ə.t ̬i/ noun [ U ] FORCE

the force which attracts objects towards one another, especially the force that makes things fall to the ground

the laws of gravity

• proportional /prəˈpɔː.ʃən.əl/ adj ( proportionate ): cân xứng

If two amounts are proportional, they change at the same rate

so that the relationship between them does not change

Weight is proportional to size

• perceptible /pəˈsep.tə.bl ̩/ /pɚ-/ adjective

that can be seen, heard or noticed

There was a barely perceptible movement in his right arm

Gravity

• overwhelmingly /ˌəʊ.vəˈwel.mɪŋ.li/ /ˌoʊ.vɚ-/ adverb

strongly or completely; in an overwhelming way

The team were overwhelmingly defeated in yesterday's game

• inconsequential /ɪnˌkɒn t  .sɪˈkwen t  ʃ ə l/ adjective

not important

an inconsequential matter/remark

Gravity

• Gravity is a fundamental property of matter, and it

is the weakest of the 4 natural forces All objects attract each other with a gravitational force

proportional to their mass It takes a great deal of mass to generate a perceptible gravitational force The mass of the earth is overwhelmingly large in comparison to any objects within our scale of

reference The gravitational force generated by the earth is proportional to the mass of the earth The gravitational forces generated by objects on the

earth are inconsequential in comparison to the

earth‘s gravity

force /fɔːs/

• The force of (earth) gravity is strong enough at the surface, to accelerate objects toward the center of the earth at a rate of 9.8 meters per second An

object in free fall near the surface of the earth will increase in velocity by 9.8 meters per second, every second that it continues to fall

• How fast will a falling object be traveling after 5

seconds of free fall?

Mass: /mæs /

• the property of a body that causes it to have

weight in a gravitational field

force /fɔːs/

• force /fɔːs/ /fɔːrs/ noun PHYSICAL POWER

[ U ] physical, especially violent, strength or power

The force of the wind had brought down a great

many trees in the area

• force /fɔːs/ /fɔːrs/ verb [ T ] USE PHYSICAL POWER

to use physical strength or effort to make

something move or open

Move your leg up gently when you're doing this

exercise, but don't force it

force /fɔːs/

• squeeze /skwiːz/ verb PRESS TOGETHER

[ T ] to press something firmly, especially from all sides in order

to change its shape, reduce its size or remove liquid from it

Cut the lemon in half and squeeze the juice into the bowl

• invariably /ɪnˈveə.ri.ə.bli/ adverb: always

The train is invariably late

• motion /ˈməʊ.ʃ ə n/ /ˈmoʊ-/ noun MOVEMENT

[ C or U ] the act or process of moving, or a particular action or movement

The violent motion of the ship upset his stomach

force /fɔːs/

• velocity /vəˈlɒs.ɪ.ti/ /-ˈlɑː.sə.t ̬i/ noun [ C or U ] FORMAL

the speed at which an object is travelling

Light travels at the highest achievable velocity in the universe

• balanced /ˈbæl ə n t  st/ adjective

considering all sides or opinions equally

The news programme prided itself on its balanced reporting

• suspend /səˈspend/ verb STOP

[ T ] to stop or to cause to be not active, either temporarily or permanently

the ferry service has been suspended for the day because of bad weather

force /fɔːs/

• hook /hʊk/ noun [ C ] DEVICE

a curved device used for catching or holding things, especially one fixed to a surface for hanging things on

a coat/picture hook

• magnitude /ˈmæg.nɪ.tjuːd/ /-tuːd/ noun [ U ] : độ lớn

the large size or importance of something

They don't seem to grasp the magnitude of the problem

force /fɔːs/

• resulting /rɪˈzʌl.tɪŋ/ adjective [ before n ] ( FORMAL resultant )

caused by the event or situation which you have just mentioned

The tape was left near a magnetic source, and the resulting

damage was considerable

• wire /waɪə r / /waɪr/ noun METAL THREAD

[ C or U ] a piece of thin metal thread which can be bent, used for fastening things and for making particular types of objects that are strong but can bend

a wire fence

force /fɔːs/

• Just what does a force do? Suppose you squeeze a balloon without breaking it The obvious result is that you change its shape If you kick a ball it starts moving A moving body can be brought to rest by application of a force Force is invariably connected

to motion in physics Or the direction of speed of a moving body can be changed by application of a

force

• An unbalanced force changes the state of constant velocity including zero velocity of a body on which it acts Forces may be balanced or unbalanced An

iron ball suspended from a hook by a wire [Figure

(a) shown below] has two forces acting on it, its

weight, acting vertically downward and the tension acting on the wire vertically upward Since these

forces are equal in magnitude and opposite in

direction, their resultant is zero Figure (b) and (c) below show that when the resultant of a group of forces acting on the same object is zero, the forces are balanced When the resultant is not equal to

zero, the resultant is an unbalanced force

weight /weɪt/

• weight /weɪt/ noun INFLUENCE

[ U ] respect, influence, trust or importance

Her experience does give her opinions quite a bit of weight

• weight /weɪt/ verb [ T ]

to fasten something heavy to something

Paper tablecloths need to be weighted down or they tend to

blow away in the wind

weight /weɪt/

• associate /əˈsəʊ.si.eɪt/ /-ˈsoʊ-/ verb [ T ]

to connect someone or something in your mind with someone

or something else

Most people associate this brand with good quality

• payload /ˈpeɪ.ləʊd/ /-loʊd/ noun [ C ]

the amount of goods or people which a vehicle, such as an

aircraft, can carry, or the explosive which a missile carries, or the equipment carried in a spacecraft

weight /weɪt/

• freight /freɪt/ noun [ U ]

goods, but not passengers, that are carried from one place to another, by ship, aircraft, train or truck, or the system of

transporting these goods

The ship carries both freight and passengers

• rotate /rə ʊ  ˈteɪt/ /ˈroʊ.teɪt/ verb

[ I or T ] to (cause to) turn in a circle, especially around a fixed point

Rotate the handle by 180° to open the door

• board /bɔːd/ /bɔːrd/ noun TRANSPORT

on board

on a boat, train or aircraft

• Weight is a force, and a force is a vector quantity having both a magnitude and a direction associated with it

For an airplane, weight is always directed towards the center of the earth The magnitude of this force

depends on the mass of all of the parts of the airplane itself, plus the amount of fuel, plus any payload on

board (people, baggage, freight, ) The weight is

distributed throughout the airplane, but we can often think of it as collected and acting through a single point called the center of gravity In flight, the airplane

rotates about the center of gravity, but the direction of the weight force always remains toward the center of the earth During a flight the aircraft burns up its fuel,

so the weight of the airplane constantly changes Also, the distribution of the weight and the center of gravity

can change, so the pilot must constantly adjust the

controls to keep the airplane balanced.

weight /weɪt/

• overcome /ˌəʊ.vəˈkʌm/ verb overcame , overcome DEAL WITH

[ I or T ] to defeat or succeed in controlling or dealing with

something

Juventus overcame Ajax in a thrilling match

• revolutionize , UK USUALLY revolutionise /ˌrev.əˈluː.ʃ ə n.aɪz/ verb

[ T ] : cách mạng hóa

to completely change something so that it is much better

Newton's discoveries revolutionized physics

weight /weɪt/

• magnetic /mægˈnet.ɪk/ /-ˈnet ̬-/ adjective OBJECT

with the power of a magnet

• levitation /ˌlev.ɪˈteɪ.ʃ ə n/ noun [ U ] : sự bay lên

• be opposed to sth

to disagree with a principle or plan

She's opposed to religious education in schools

• Flying involves two major problems; overcoming

the weight of an object by some opposing force, and controlling the object in flight Both of these

problems are related to the object's weight and the location of the center of gravity The dream remains that, if we could really understand gravity, we could create anti-gravity devices which would

revolutionize travel through the sky Unfortunately, anti-gravity devices only exist in science fiction

Machines like airplanes, or magnetic levitation

devices, create forces opposed to the gravitational force, but they do not block out or eliminate the

gravitational force

the vertical force exerted by a mass as a result of

gravity

what is pressure?

• pressure /ˈpreʃ.ə r / /-ɚ/ noun PUSH

[ U ] the force you produce when you press something

He put too much pressure on the door handle and it snapped

gas/water pressure

The new material allows the company to make gas pipes which

withstand higher pressures

The gas is stored under pressure (= in a container which keeps it

at a higher pressure than it would usually have)

• pressure /ˈpreʃ.ə r / /-ɚ/ verb [ T ] MAINLY US

to strongly persuade someone to do something they do not want to

do

She was pressured into joining the club

• Pressure is defined as force divided by the area on

which the force is pushing (See the lesson on

Pressure for details.) You can write this as an

equation, if you wanted to make some calculations:

• exert /ɪgˈzɜːt/ /-ˈzɝːt/ verb USE

[ T ] to use something such as authority, power, influence, etc in order to make something happen

If you were to exert your influence they might change their

decision

• sole /səʊl/ /soʊl/ noun [ C ] FOOT

plural soles the bottom part of a foot which touches the ground

when you stand or walk, or the bottom part of a shoe which touches the ground, usually not including the heel

linear /ˈlɪn.i.ə r / /-ɚ/ adjective LINES

consisting of or to do with lines

a linear diagram

• momentum /məˈmen.təm/ /-t ̬əm/ noun [ U ]

the force that keeps an object moving or keeps an event developing after it has started

Once you push it, it keeps going under its own momentum

• perpendicular /ˌpɜː.p ə nˈdɪk.jʊ.lə r / adjective

FORMAL at an angle of 90° to a horizontal line or surface

Pressure due to gravity

• Since the weight of an object or material is equal to the

force it excerts due to gravity,

• An object can exert downward pressure due to its weight and the force of gravity The pressure you exert on the floor

is your weight divided by the area of the soles of your

shoes If the force is due to the weight (W) of the object, the equation is then: P = W / A

Water pressure

• The water pressure at the bottom of a lake is equal to the weight of the column of water above divided by the area of that column

Pressure and pascal ‘s law:

• Total Force = (pressure)(area)

• TF = pA