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Conversely, a spherical wave generated by a point source placed in the focus is transformed into a plane wave propagating as a collimated beam along the axis.

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## Some Related Sentences

Conversely and wave

__Conversely__

**,**if

**the**

**source**of waves

**is**moving away from

**the**observer

**,**each

__wave__

**is**emitted from

**a**position farther from

**the**observer than

**the**previous

__wave__

**,**so

**the**arrival time between successive waves

**is**increased

**,**reducing

**the**frequency

**.**

__Conversely__

**,**

**the**beach profile

**is**lower

**in**

**the**winter due to

**the**increased

__wave__energy associated with storms

**.**

__Conversely__

**,**during reception

**,**

**the**oscillating electric and magnetic fields of an incoming radio

__wave__exert force on

**the**electrons

**in**

**the**antenna elements

**,**causing them to move back and forth

**,**creating oscillating currents

**in**

**the**antenna

**.**

__Conversely__

**,**an incoming

**plane**

__wave__parallel to

**the**

**axis**will be focused to

**a**

**point**at

**the**focal

**point**

**.**

__Conversely__

**,**if waves of different frequencies are not coherent

**,**then

**,**when combined

**,**they create

**a**

__wave__that

**is**continuous

**in**time ( e

**.**g

**.**white light or white noise ).

__Conversely__

**,**

**a**high PRR / PRF can enhance target discrimination of nearer objects such

**as**

**a**periscope or fast moving missile leading to practices of employing low PRRs for search radar

**,**and very high PRFs for fire control radars

**,**with many dual-purpose and navigation radars

**,**especially naval designs having variable PRRs which might allow

**a**skilled operator to also use

**a**PRR adjustment to enhance and clarify

**a**unclear radar picture

**,**for example

**in**bad sea states where

__wave__action generates false returns

**,**and

**in**general for less clutter

**,**or perhaps

**a**better return signal off

**a**prominent landscape feature ( e

**.**g

**.**

**a**cliff ).

__Conversely__

**,**

**a**system which changes

**the**shape of

**the**

__wave__( beyond simple scaling or shifting ) creates additional harmonics ( harmonic distortion ).

__Conversely__

**,**

**the**density determines

**the**

__wave__function modulo

**a**phase factor

**,**providing

**the**formal foundation of density functional theory

**.**

Conversely and generated

)

__Conversely__**,**if B satisfies both of**the**conditions 1 and 2**,**then there**is****a**unique topology on X for which B**is****a**base ; it**is**called**the**topology__generated__**by**B**.**__Conversely__

**,**every context-sensitive language which does not generate

**the**empty string can be

__generated__

**by**

**a**grammar

**in**Kuroda normal form

**.**

In two dimensions

**,****the**finite reflection groups are**the**dihedral groups**,**which are__generated__**by**reflection**in**two lines that form an angle of and correspond to**the**Coxeter diagram__Conversely__**,****the**cyclic**point**groups**in**two dimensions are not__generated__**by**reflections**,**and indeed contain no reflections – they are however subgroups of index 2 of**a**dihedral group**.**

Conversely and by

__Conversely__

**,**most realists ( specifically

**,**indirect realists ) hold that perceptions or sense data are caused

__by__mind-independent objects

**.**

__Conversely__

**,**paintings which came out of his workshop that were not necessarily physically worked on

__by__Cuyp but merely overseen

__by__him technically

**,**were marked with A

**.**C

**.**to show that it was his instruction which saw

**the**paintings ’ completion

**.**

__Conversely__

**the**use of true brass seems to have declined

**in**Western Europe during this period

**in**favour of gunmetals and other mixed alloys but

__by__

**the**end of

**the**first Millennium AD brass artefacts are found

**in**Scandinavian graves

**in**Scotland

**,**brass was being used

**in**

**the**manufacture of coins

**in**Northumbria and there

**is**archaeological and historical evidence for

**the**production of brass

**in**Germany and The Low Countries areas rich

**in**calamine ore which would remain important centres of brass making throughout

**the**medieval period

**,**especially Dinant – brass objects are still collectively known

**as**dinanterie

**in**French

**.**

__Conversely__

**,**if

**a**Boolean ring A

**is**given

**,**we can turn it

**into**

**a**Boolean algebra

__by__defining x ∨ y := x + y + ( x · y ) and x ∧ y := x · y

**.**

__Conversely__

**,**because space

**is**expanding

**,**and more distant objects are receding ever more quickly

**,**light emitted

__by__us today may never " catch up " to very distant objects

**.**

__Conversely__

**,**Fleet Captain Honoré Ganteaume later reported

**the**cause

**as**an explosion on

**the**quarterdeck

**,**preceded

__by__

**a**series of minor fires on

**the**main deck among

**the**ship's boats

**.**

__Conversely__

**,**these arguments were disputed

__by__those who claimed Dominion was widely misunderstood

**,**and conservatively inclined commenters saw

**the**change

**as**part of

**a**much larger attempt

__by__Liberals to " re-brand " or re-define Canadian history

**.**

__Conversely__

**,**an absence of secure cycle-parking

**is**

**a**recurring complaint

__by__cyclists from cities with low modal share of cycling

**.**

__Conversely__

**,**

**the**end of

**the**Cold War marked

__by__

**the**fall of

**the**Berlin Wall

**in**1989 resulted

**in**

**a**reduction

**in**

**the**duration of Cold War civil wars of 92 % or

**,**phrased another way

**,**

**a**roughly ten-fold increase

**in**

**the**rate of resolution of Cold War civil wars

**.**

__Conversely__

**the**car

**is**stopped

__by__releasing pressure on

**the**cable ( with or without completely detaching ) and applying

**the**brakes

**.**

__Conversely__

**,**factors that favor plate columns are: presence of solids

**in**feed

**,**high liquid rates

**,**large column diameters

**,**complex columns

**,**columns with wide feed composition variation

**,**columns with

**a**chemical reaction

**,**absorption columns

**,**columns limited

__by__foundation weight tolerance

**,**low liquid rate

**,**large turn-down ratio and those processes subject to process surges

**.**

__Conversely__

**,**non-spontaneous electrochemical reactions can be driven forward

__by__

**the**application of

**a**current at sufficient voltage

**.**

__Conversely__

**,**badly managed food aid can create problems

__by__disrupting local markets

**,**depressing crop prices

**,**and discouraging food production

**.**

__Conversely__

**,**when one wants to compute an arbitrary number ( N ) of discrete samples of one cycle of

**a**continuous DTFT

**,**it can be done

__by__computing

**the**relatively simple DFT of s < sub > N </ sub >,

**as**defined above

**.**

__Conversely__

**,**one might expect that inertial motions

**,**once identified

__by__observing

**the**actual motions of bodies and making allowances for

**the**external forces ( such

**as**electromagnetism or friction ), can be used to define

**the**geometry of space

**,**

**as**well

**as**

**a**time coordinate

**.**

__Conversely__

**,**when

**a**piece of land

**is**separated from

**the**mainland

__by__

**a**man-made canal

**,**for example

**the**Peloponnese

__by__

**the**Corinth Canal

**,**it

**is**generally not considered an island

**.**

__Conversely__

**,**people who revere or venerate religious images are (

__by__iconoclasts ) called " iconolaters ".

__Conversely__on occasions he attracted criticism for dogmatically pursuing schemes favoured

__by__

**the**right of his party

**,**notably

**the**privatisation of British Rail

**,**and for closing down most of

**the**coal industry

**in**advance of privatisation

**.**

__Conversely__

**,**Trotsky held that socialism

**in**one country would economically constrain

**the**industrial development of

**the**USSR

**,**and thus required assistance from

**the**new socialist countries that had arisen

**in**

**the**developed world

**,**which was essential for maintaining Soviet democracy

**,**

**in**1924 much undermined

__by__civil war and counter-revolution

**.**

Given

**a**field ordering ≤**as****in**Def 1**,****the**elements such that x ≥ 0 forms**a**positive cone of F**.**__Conversely__**,**given**a**positive cone P of F**as****in**Def 2**,**one can associate**a**total ordering ≤< sub > P </ sub >__by__setting x ≤ y to mean y − x ∈ P**.**This total ordering ≤< sub > P </ sub > satisfies**the**properties of Def 1**.**

Conversely and point

__Conversely__

**,**if he gives

**a**heavy rating to his own reading

**,**and finds more accurate facts

**in**it than

**in**

**the**others

**,**

**a**

__point__

**is**chalked up for

**the**intrinsic

**,**objective meaningfulness of this type of mediumistic material

**.**

__Conversely__

**,**every

__point__on

**the**line can be interpreted

**as**

**a**number

**in**an ordered continuum which includes

**the**real numbers

**.**

__Conversely__

**,**there are other stars that never rise above

**the**horizon

**,**

**as**seen from any given

__point__on

**the**Earth's surface ( except exactly on

**the**equator ).

__Conversely__

**,**Salinger

**is**reported to have considered

**the**story

**a**" high

__point__of his writing " and made tentative steps to have it reprinted ; these efforts came to nothing however

**.**

__Conversely__

**,**observers looking toward

**the**same

__point__on an infinite-radius celestial sphere will be looking

**along**parallel lines

**,**and observers looking toward

**the**same great circle

**,**

**along**parallel planes

**.**

)

__Conversely__**,****a**critical__point__x of f can be analysed**by**considering**the**second derivative of f at x:__Conversely__

**,**

**the**influence of

**the**data at any given

__point__on

**the**initial line propagates with

**the**finite velocity c: there

**is**no effect outside

**a**triangle through that

__point__whose sides are characteristic curves

**.**

__Conversely__

**,**

**a**disease that

**is**easily transmitted but has

**a**short duration might spread widely during 2002 but

**is**likely to have

**a**low prevalence at any given

__point__

**in**2003 ( due to its short duration ) but

**a**high incidence during 2002 (

**as**many people develop

**the**disease ).

__Conversely__

**,**

**a**

__point__

**source**at

**the**

**focus**of

**a**parabolic mirror will produce

**a**

**beam**of

**collimated**light creating

**a**Collimator

**.**

__Conversely__

**,**

**a**system past

**the**critical

__point__will experience too many blackouts leading to system-wide upgrades moving it back below

**the**critical

__point__

**.**

Any

__point__x gives rise to**a**continuous function p < sub > x </ sub > from**the**one element topological space 1 ( all subsets of which are open ) to**the**space X**by**defining p < sub > x </ sub >( 1 ) = x**.**__Conversely__**,**any function from 1 to X clearly determines one__point__:**the**element that it " points " to**.**
A tangent

**plane**can be " rolled "**along**S**,**and**as**it does so**the**__point__of contact traces out**a**curve on S**.**__Conversely__**,**given**a**curve on S**,****the**tangent**plane**can be rolled**along**that curve**.**
which are linearly independent at each

__point__q**in**U**.**__Conversely__**,**given such**a**coframe**,**there**is****a**unique moving frame X < sub > 1 </ sub >, X < sub > 2 </ sub >, ..., X < sub > n </ sub > which**is**dual to it**,**i**.**e., satisfies**the**duality relation α < sup > i </ sup >( X < sub > j </ sub >) = δ < sup > i </ sup >< sub > j </ sub >, where δ < sup > i </ sup >< sub > j </ sub >**is****the**Kronecker delta function on U**.**__Conversely__

**the**normal curvature

**is**

**the**norm of

**the**projection of on

**the**normal bundle to

**the**submanifold at

**the**

__point__considered

**.**

)

__Conversely__**,**given**a**__point__**,****the**logarithm gives**a**__point__**in****the**tangent space ( roughly speaking**,****as**again**,**one must transport from**the**origin to__point__; for details**,**refer to original sources ).0.259 seconds.