SIDA LOO SAMEEYO WEBSITE FREE AH LOOGANA HELO BISHII LACAG DHAN $1000. CASHARKA 1 AAD

 

SIDA LOO SAMEEYO WEBSITE FREE AH LOOGANA HELO BISHII LACAG DHAN $1000. CASHARKA 1 AAD

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Siyaabaha aad ku hagaajin karto caafimaadkaaga shucuurta oo aad ku ilaaliso nolol dheelitiran

 

 Siyaabaha aad ku hagaajin karto caafimaadkaaga shucuurta oo aad ku ilaaliso nolol dheelitiran

Caafimaad qab niyadeed macnaheedu maaha in qofku faraxsan yahay mar kasta. Waxay la macno tahay inaad si fiican u garanayso shucuurtaada. Waad la tacaali kartaa, ha ahaato mid togan ama mid taban. Xaqiiqooyinka ugu muhiimsan ee WHO waxay sheegaysaa in saamaynta daawaynta la'aanta arrimaha caafimaadka maskaxda ee qaan-gaarka ah ay gaareyso qaan-gaarnimada, wax u dhimaysa caafimaadka jireed iyo nafsiyeed labadaba, iyo xaddididda fursadaha lagu noolaado nolol macno leh.

 

Cilmi-baadhis ay sameeyeen khubarada cilmu-nafsiga ee magaalada New York ayaa sheegaya in ay aad ugu fududahay in lala qabsado nolosha yar ee kor u kaca iyo hoos u dhaca iyo dhacdooyinka muhiimka ah marka qofku uu naftiisa ku wanaagsan yahay. Xataa marka ay noloshu isku dheeli tiran tahay, wax walbana ay u socdaan si habsami iyo hufnaan leh, waxa imanaysa wakhti aanu dareemayno culaysyo badan, wakhtiyada aynu ognahay waa in aynu joojinaa oo aynu ku dadaalnaa in aynu miisaan wayn ku dadaalno. Way adag tahay in la sii wado. Si kastaba ha ahaatee, ha ka welwelin haddii aad ku jirto booskaas; waxaad ugu danbayn halkaas gaadhaysaa oo aad gaadhaysaa yoolkaaga.

 

 

 

Ku celcelinta iyo ka shaqaynta xakamaynta shucuureed

La qabsiga shucuurta ku salaysan waxay kaa caawinaysaa inaad daryeesho dareenkaaga marka midkoodna aanad doonayn inaad beddesho xaaladaada ama marka ay xaaladuhu ka baxsan yihiin xakamayntaada. Tusaale ahaan, haddii aad ka murugoonayso waayitaanka qof aad jeceshahay, waxa ay noqon doontaa muhiim inaad u daryeesho dareenkaaga hab caafimaad leh (maadaama aadan bedeli karin xaaladda).

 

Had iyo jeer ma jirto hal dariiqo oo ugu wanaagsan oo lagu sii wado. Taa beddelkeeda, adiga ayay kugu xiran tahay inaad go'aansato xirfadda la qabsiga ee ay suurtogal tahay inay sida ugu fiican kaaga shaqeyso xaalad gaar ah.

 

Qaado Maalin Fasax

Si hufan u maamul wakhtigaaga adoo dejinaya yoolalka

Jadwal waa la ilaalin karaa, hadafyadana waa la dejin karaa usbuuca. Marka qofku ka gudbo liiska wax-qabadka, waxaa jira dareen guul leh oo kaa caawin doona dhimista walaaca iyo kordhinta kalsoonida.

 

Ku celcelinta Maskaxda

 

Maskaxda waxaa loo tixgeliyaa dhaqan qadiimi ah. Waa in si buuxda looga warqabo waxa hadda ka dhacaya oo gudaha iyo hareerahaaga ka socda. Fikradda ugu weyn waa inaadan noloshaada ugu noolaan "qaabka autopilot" laakiin aad noqoto qof aad u feejigan.

 

Waa kuwan sida aad ugu dhaqmi karto miyir-qabka:

 

Ku celceli neefsashada qoto dheer si joogto ah. Diirada saarista neeftaada waxay xoojisaa feejignaanta iyo dhiirigelinta.

Bar dhaqanka socodka: Qofku marka uu socdo oo uu arko muuqaalada iyo dhawaaqyada ku hareeraysan, fikrado badan ayaa maskaxda gala. Dhaqanka lagama maarmaanka ah ayaa ah in la xuso, ka dibna lagu noqdo wakhtigan.

 

xooji Xidhiidhkiina Bulsho ahaan

 

Xidhiidhada bulshadu waxa ay kaa caawinayaan ilaalinta caafimaadkaaga oo cimriga dheereeya. Waxaa si weyn loo rumeysan yahay in xiriirka wanaagsan ee lala yeesho dadka kale uu saameyn xooggan ku yeelan karo caafimaadkeenna - naf ahaan iyo jir ahaanba. Haddi ay noqoto lammaaneheena jacaylka, qoyska, asxaabta, jaarka, ama kuwa kale, xidhiidhka bulshadu waxa uu si toos ah u saamayn karaa bayolojiyada iyo fayoobideena.

 

Maskaxda ku hay Qodobbadaada Wanaagsan

 

Dhammaanteen waxaynu leenahay meelaha aynu ku wanaagsannahay iyo meelaha ay ku liidato, mana jiro mid naga mid ah oo qumman sidoo kale. Way sahlan tahay in lagu fekero in kuwa kale ay yihiin kuwo karti badan, guulo badan, oo ay leeyihiin fursado badan oo naga badan marka arrimuhu ay socon waayaan jidkayaga. Wax kasta oo ay u ekaan karto dusha sare, waa wax aan suurtagal ahayn in la ogaado sida uu qof dareemayo gudaha. Waa in qofku is xasuusiyo waxyaalaha aad si fiican u qabato oo aad ugu fiican tahay, ugu dambayntiina isu dheellitiridda fikradaha muhiimka ah ee naftaada ku saabsan. Xasuusnoow inaad muhiim tahay, iyo inaad si wanaagsan u daryeesho caafimaadkaaga shucuureed ayaa ugu dambeyntii kor u qaadi doonta fayoobidaada guud.

 

Mudooyinkii ugu dambeeyay, cudurka faafa awgeed, caafimaadka dhimirku aad buu u xumaaday. Cilmi baaris ayaa muujisay in walwalka iyo niyad-jabka ay ku soo badanayaan dadweynaha guud ahaan, iyadoo mid ka mid ah saddexdii qofba uu la kulmay walaac, shantii qofba mid ayaa la kulma hurdo la'aan iyo calaamado niyad-jab ah. Waa lama huraan in bini'aadamku dareemo murugo, walaac, loolan, niyad jab, ama si fudud u niyad jabsan oo aanu awoodin inuu la qabsado wakhtiyadan aan la hubin.

 

Baahida saacadu waa in la helo caafimaad shucuureed, maskaxiyan degan, oo la horumariyo xeelado laqabsiga ka wanaagsan. Waxaad heli kartaa farxadaas iyo fayoobaanta guud ee aad had iyo jeer u xiisayn jirtay. Helitaanka baadhis qotodheer oo caafimaadka dhimirka ah ayaa kaa caawin doonta sahaminta meelaha aad u baahan tahay inaad ka shaqeyso. Kadib waxaad heli kartaa qalab is-caawin ah ama waxaad ballan ka qabsan kartaa daaweeyaha kaa caawin kara inaad u hesho dariiqa fayoobida maskaxda. Marka hore ee aad gaadho, si fiican ayaad u dareemaysaa.

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4 Talooyin loogu talagalay Qorshaha dhimista Miisaanka

1-      Tallaabada ugu horreysa ee miisaan lumis caafimaad leh waa in la abuuro nooc ka mid ah qorshe miisaan lumis.

Tani waa wax ay tahay in lagu tixgeliyo qorshahaaga miisaan dhimista. Sideed guud ahaan noloshaada uga dhigi doontaa mid wanaagsan? Immisa siyaabood ayaad u wajihi kartaa "miisaan dhimista"? Ha ka dhigin hadafkaaga inaad lumiso rodol badan usbuucan. Halkii, deji hadaf aad ku socotid daqiiqado badan, kor u qaad rodol badan, beer daqiiqado badan. Habkaas, xitaa haddii aanu miisaankaagu wax badan iska beddelin muddadaas ama xitaa u socdo jihada qaldan, waxaad weli ogtahay in jidhkaagu uu ka faa'iideysanayo qaybaha qorshahaaga miisaan dhimista ee aad weli la xiriirto.

 

FIIRO GAAR AH: Dadka bilaabay jimicsiga qayb ka mid ah barnaamijkooda miisaan dhimista waxay inta badan la kulmaan miisaan kor u kaca toddobaadyada ugu horreeya ee khibraddooda jimicsiga cusub. Tani waa si sax ah oo dabiici ah! Haddii aad hadda bilowday jimicsi si aad miisaanka u lumiso oo aad la kulanto miisaan korodh, tani waa inay ahaato mid ku meel gaar ah, waxaana inta badan sababa jidhkaaga oo ku dara cufnaanta muruqa si ka dhakhso badan inta uu luminayo baruurta.

 

2- Qorshee in aad aayar u socotid:

 

Ma garanayo haddii ay jirto tirokoob meel ka mid ah oo muujinaya inta qof ee ka tagay barnaamijkooda miisaan dhimista walaaca, cadaadiska, xanuunka, ama gubasho cad. Si kastaba ha ahaatee, aniga lafteyda ayaan la kulmay, waan ka akhriyay, dadkana waan ogahay inay ku dhacday. Mararka qaarkood weedhaha ugu fudud ayaa ah kuwa ugu run ah. Mid aad inta badan maqli doonto ayaa ah, "Waxay ku qaadatay sannado in jidhkaagu sidan ku helo, mana beddeli kartid hal habeen." Tani waa run. Sidoo kale, tixgeli in, inkastoo laga yaabo inaadan ARAGNIN isbeddello la taaban karo, haddii aad qaadayso tillaabooyinka aad ku qeexday qorshahaaga dhimista miisaanka, jidhkaagu wuxuu la qabsanayaa gudaha, meelo aadan arki karin, laakiin wuu hagaajinayaa oo wuu hagaajinayaa. isu diyaarinta in aad u gudubto heerarka sare ee jirdhiska iyo caafimaadka.

 

3- Qorshee si aad u cabbirto horumarkaaga:

Waan ogahay in aan idhi ha ka welwelin miisaanka dhimista, laakiin waxaad u baahan tahay inaad aragto waxa socda. Uma baahnid inaad si gaar ah diiradda u saarto rodolyada lumay, si kastaba ha ahaatee. Haddii aad usbuucan aad uga sii fogaan karto laba ama saddex toddobaad ka hor, horumar baad samaynaysaa. Waxaan rajeyneynaa, laba toddobaad oo kale, inaad sii socon doonto, ama aad dhaqso badan tahay. Haddii, bilawga barnaamijka miisaankaaga dhimista, kaliya waxaad samayn kartaa jimicsi shan daqiiqo ah markiiba, oo hadda waxaad samayn kartaa jimicsi 15 daqiiqo, taasi waa horumar, miyaanay ahayn? Taasi waa guul, waana wax ay tahay inaad ku faanto.

 

FIIRO GAAR AH: Hal cabbir oo lagu cabbiro horumarka laga gaaray barnaamijka miisaan dhimista ayaa si fudud u ah "xajmiga". Laba toddobaad oo barnaamijka miisaanka dhimista, waxaa laga yaabaa inaad dhab ahaantii miisaan korodhay, tusaale ahaan, sida aan tilmaamay dhowr cutub ka hor. Si kastaba ha ahaatee, haddii dharkaagu dabacsan yahay, ama aad u baahan tahay inaad iibsato dhar yaryar, ama saaxiibo ayaa soo socda oo weydiinaya, "Miyaad lumisay miisaanka?" Kuwani waa calaamado wanaagsan oo muujinaya in barnaamijkaagu shaqeynayo xitaa haddii miisaankaagu uusan weli helin warka.

 

 

4- Qorshee inaad dhiirigeliso:

 

Mid ka mid ah caqabadaha ugu badan ee dadka ka saaraya barnaamijkooda miisaan dhimista waa lumitaanka dhiirigelinta. Dareenka iyo xamaasadda kugu bilaaba waa dhif iyo naadir marka aad xirto kabahaaga socodka wax u eg markii milyanaad oo aad lumisay laba rodol oo keliya.

 

Marka lagu daro sababahaaga dhimista miisaanka, dareenka iyo malaha kicinta jirka ee kugu bilaabay meesha ugu horeysa, iyada oo qayb ka ah qorshahaaga miisaan dhimista ee qoran waxay ku siinaysaa hab aad dib ugu soo kiciso rabitaankaaga si aad u gaarto yoolalkaaga. Inta badan waxaynu illownaa sida aanu dareemaynay iyo wixii aanu rumaysnay bilawgii safarkan oo kale, in aanu awood u yeelano in aanu warqada ka soo saarno oo aanu dib u eegno riyooyinka iyo waxa laga filayo waxa ay dib inoogu soo celin kartaa heerkaas asalka ah, ama ugu yaraan waxa ay ina xasuusin kartaa waxa aanu nahay. waxay u adkaysanayaan tan.

 

Waxaan macalin u ahaan jiray shirkad weyn oo qaran, hal shay oo aniga iyo macalimiinta kaleba aan u sheegi lahayn ardaydeena, si ay u gaaraan hadafkooda, waxay ahayd inay "qorsheeyaan shaqadooda, oo ay sameeyaan qorshahooda." 

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Sidee ku fahmi karaa ku hadalka English ka

 

1_ Ugu horeyn aamin naftaada

Naftaada sii wakhti aad kula qabsato lahjadda qofka - iyo sidoo kale siyaabaha ay dadka ku hadla afka hooyo u adkeeyaan erayada qaar, yareeyaan dhawaaqyada kale, iskuna xidhaan dhawaaqyada.
2_ Noqo dhegeyste firfircoon
Si aad si fiican u fahamto kuwa ku hadla afka hooyo, waxaad u baahan tahay inaad xoogga saarto markaad dhegaysanayso. Kuma filna inaad ka fikirto in xirfadahaaga dhegaysigu ay fiicnaan doonaan haddii aad kaliya haysato raadiyaha Ku celceli dhegeysiga si joogto ah Tani waxay la mid tahay barta 1 ee sare. Hagaajinta xirfadahaaga dhegeysi si aad u fahmi karto dadka ku hadla afkooda hooyo ee Ingiriisigu waxay qaadataa waqti - iyo ku celcelinta. Haddii ay kugu adag tahay, dhegayso dhawr daqiiqo maalintii - maalin kasta. Kadib marka ay kuu fududaato, waxaad dhagaysan kartaa wakhti dheer. Wax macno ah ma leh waxaad dhagaysato - kartoonnada, qaybo ka mid ah filimada, podcasts, fiidiyowyada YouTube waxay dhammaantood kaa caawin doonaan "tababarida dhegtaada" si aad u sii isticmaasho qaababka Ingiriisiga lagu hadlo.

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Sida Tignoolajiyadu u Hormariso E-commerce Kobaca Ganacsiga

 

Sida Tignoolajiyadu u Hormariso E-commerce Kobaca Ganacsiga

Tignoolajiyada ayaa ah tiirka ugu weyn ee ganacsiga e-commerce. Waxay ku xidhaa iibiyeyaasha iyo macaamiisha aaladaha mobilada iyo shabakada. Waxay fududaynaysaa dalabka macmiilka, Soo dirida Martida, soo celinta, iyo maamulka lacag bixinta si aan buuq lahayn. Guud ahaan, tignoolajiyada ayaa door muhiim ah ka ciyaara inta lagu jiro silsiladda qiimaha e-commerce ee suuq-geynta, xayeysiinta, iyo meelaha kale. Tignoolajiyada ku jirta e-commerce waxay awood u siisaa raadinta korodhka, habaynta, iyo shaqsiyaynta. Maalmahan, tignoolajiyada horumarsan ayaa wax u fududeynaya ciyaartoyga e-commerce waxayna gaarayaan heerar muhiim ah oo caan ka ah silsiladda qiimaha e-ganacsiga. Sida ku cad warbixinnada horumarinta e-commerce ee shirkadda cilmi-baarista eMarketer, iibka e-commerce ee caalamiga ah wuxuu gaaray 4.1 tiriliyan iyo 4.5 tiriliyan US dollars 2020 iyo 2021, siday u kala horreeyaan. Isla isbeddelku waxay u badan tahay inuu ku sii socdo kobaca la filayo ee $ 5 trillion ee 2022. Soo hel macluumaadka shanta tignoolajiyada ee soo baxaya ee saamaynta ugu badan ku yeelan doona ganacsiga e-commerce.

Waayo-aragnimada Isticmaale ee gaarka ah ee Tignoolajiyada

Ku saabsan 74% ganacsiyada ayaa qiraya in khibradda adeegsadaha (UX) ay muhiim u tahay kordhinta iibka iyo beddelka. Ku saabsan 59% macaamiisha ayaa sheegaya in tignoolajiyada soo baxaya ay saameyn ku yeesheen go'aanadooda wax iibsiga waxayna taageereen dookhyada shakhsi ahaaneed ee macaamiisha. Marka aan ka hadalno doorka tignoolajiyada ee kobcinta kobaca ganacsiga e-commerce, waxay ka dhigan tahay saameynta tooska ah ee tignoolajiyada horumarsan ee macaamiisha 'dhaqanka iibsashada.

 

Laga soo bilaabo xogta weyn ilaa barashada mashiinka (ML) ilaa AI, dhammaan tignoolajiyada cusubi waxay bixiyaan falanqayn iyo dareen habdhaqanka macaamiisha. Tignoolajiyadu waxay kicin kartaa ololeyaal xayaysiis oo wanaagsan, isgaadhsiin toos ah, kordhinta heerarka hawlgelinta, waxayna bixin kartaa taageero iyo adeegyo.

                  Gabagabo

Doorka tignoolajiyada ee warshadaha e-commerce waa mid aan toos ahayn oo lama huraan ah. Warshadaha e-ganacsiga ayaa ku sii socon doona inay ku kobcaan isbeddellada tignoolajiyada sababta oo ah isku darka tignoolajiyada iyo hal-abuurka ayaa saameeya dhammaan warshadaha eCommerce.

 

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Ma rabtaa inaad si degdeg ah u lumiso miisaanka?

 

 

Ma rabtaa inaad si degdeg ah u lumiso miisaanka?

Miisaanka oo yaraadaa maaha jawaabta dhibaato kasta oo caafimaad, laakiin haddii dhakhtarkaagu kugula taliyo, waxaa jira talooyin kaa caawinaya inaad si badbaado leh u lumiso miisaanka. Miisaan joogto ah oo 1 ilaa 2 rodol todobaadkii ayaa lagula talinayaa maaraynta miisaanka muddada-dheer ee ugu waxtarka badan.

 

Waxaa laga yaabaa inaad ogaato inaad awood u leedahay inaad lumiso miisaanka adiga oo raacaya cunto karbohaydrayt hooseeya ama cunto diiradda saaraysa cuntooyinka oo dhan, laakiin waxaa jira mabaadi'da guud qaarkood oo khuseeya marka aad isku dayayso inaad lumiso miisaanka.

 

Sida loo lumiyo miisaanka 3 tillaabo oo fudud

1-       1-  Iska yaree karbohaydraytyada la safeeyey

Hal dariiqo oo kaa caawin kara inaad si degdeg ah u lumiso miisaanka waa inaad yareyso sonkorta ama karbohaydraytyada. Tani waxay noqon kartaa qorshe cunto cunto karbohaydh hooseeya ama iyada oo la yareeyo karbohaydraytyada la safeeyey laguna beddelo miro dhanaan.

 

2-     2-  Cun borotiinka, baruurta, iyo khudaarta

Ujeedo inaad cunto kasta ku darto cuntooyin kala duwan. Si aad isugu dheellitirto saxankaada oo ay kaaga caawiso in aad miisaankaaga dhimatid cuntooyinkaaga waa in ay ku jiraan:

 

il borotiin ah  iyo khudaarta

qayb yar oo karbohaydraytyo adag ah, sida miraha oo dhan

 

3-       3- Dhaqdhaqaaqa jirkaaga

Jimicsiga, inkastoo aan loo baahnayn inuu lumiyo miisaanka, wuxuu kaa caawin karaa inaad si dhakhso ah u lumiso miisaanka. Miisaanka qaadista waxay leedahay faa'iidooyin wanaagsan gaar ahaan.

 

Kor u qaadista miisaanka, waxaad gubi doontaa kalooriyooyinka waxayna kaa caawin doontaa inaad ka hortagto dheef-shiid kiimikaadkaaga inuu hoos u dhaco, taas oo ah saameyn caadi ah oo ay leedahay dhimista miisaanka

 

Isku day tababarka xoogga saddex ilaa afar jeer toddobaadkii. Haddii aad ku cusub tahay qaadista miisaanka, tababaraha ayaa laga yaabaa inuu kaa caawiyo inaad bilowdo. Hubi in dhakhtarkaagu sidoo kale ka warqabo qorshe kasta oo jimicsi oo cusub.

 

Haddii miisaan qaadista aysan ahayn ikhtiyaar adiga, samaynta qaar ka mid ah jimicsiga wadnaha sida socodka, orodka, orodka, baaskiil wadida, ama dabaasha ayaa aad faa'iido u leh dhimista miisaanka iyo caafimaadka guud.

 

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Waa maxay Farqiga u dhexeeya Hardware iyo Software

 Farqiga u dhexeeya Hardware iyo Softwar

Nidaamka kombuyuutarku wuxuu u qaybsan yahay laba qaybood: Hardware iyo Software. Hardware waxa loola jeedaa qaybaha jidheed iyo kuwa muuqda ee nidaamka sida Monitor, CPU, keyboard iyo mouse. Dhanka kale, Software-ku waxa uu tilmaamayaa hab-raacyo kala duwan oo awood u siinaya qalabku in uu qabto hawlo gaar ah. Software-ka waa in lagu rakibaa qalabka si uu si sax ah u shaqeeyo, si la mid ah, qalabku waa inuu jiraa si loogu talagalay hawlaha la qabanayo. Labaduba way isku tiirsan yihiin, haddana way ka duwan yihiin midba midka kale.

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Physics work, power, energy and simple machinesChapter 7

 

    Class: form one:                                                   Subject: Physics

Chapter 7

WORK,POWER, ENERGY AND SIMPLE MACHINES

7.1 work

Definition

Work is done when a force causes an object to move in the same direction that the force is applied.

We therefore measure work by measuring the applied force and distance covered.

Work=force applied x distance moved in direction of the force.

              W=fd

The unit of work is joule(j).Finance Only

Example 7.1

If you have to pull with a force of 50N to move a create steady 3m in the direction of the force, find the work.

Solution

  Work= f x d

             = 50Nx3m= 150Nm = 150N

Example 7.2

A car weighing 1000kg and traveling at 30m/s stops at distance of 50m decelerating uniformly.

What is the force exerted on it by the brakes? What is the work done by the brakes?

Solution

Given

Initial speed, u =30m /s   , Final speed, v - 0 (The car stops) ,    Acceleration, a- ? Distance, s = 50 m

We know that;

So, (0)²=(30)²+2xax50

100a= -900

a=-900/100

Thus, Acceleration, a= -9m /s

The force exerted by the brakes can now be calculated using the formula

F= mxa

Here, Mass, m = 1000 kg   And, Acceleration, a= -9m /s (Calculated above)

So, Force, F =1000x(-9)

F=-9000N

The work done by the brakes can be calculated by using the relation: W = Fxd

Here, Force, F= 9000 N Distance, d = 50m

So, Work done, W= 9000 x 50 J

= 450000 J

= 4.5 x 10⁵ J

Thus, the work done by the brakes is 4.5 x 10 joules.

7.1.1 Work done against the gravity

The amount of work done is equal to the product of weight of the body and the vertical distance through which the body is lifted.

Now, Work done in lifting a body = Weight of body x Vertical distance

W=m x g x h

where; W = work done.

m = mass of the body.   g = acceleration due to gravity.   and h = height through which the body is lifted.

Example 7.3

Calculate the work done in lifting 200 kg of water through a vertical height of 6 metres (Assume g = 10 m/s?).

Solution

Given: m=200kg h=6m, g=10m/s w=?

W=mgh

W = 200kg x 10m /s x 6m

W=12000j

7.2 power

Definition: Power is the rate at which work is done or the rate at which energy is transferred from one place to another.

Mathematically, it can be denoted as follows;

p=power        w=work      be time

Unit of power

The SI unit of power is Watt in honor of the Scottish mechanical engineer, James Watt, Watt is most famous for inventing an improved steam engine.

W= j/s

Other units of power are

Kilowatt (Kw) =1000W        Megawatt (Mw) =10⁶w    Horsepower (Hp) =746W=750W

Example 7.4

An elevator with an operator weighs 5000 N. If it is raised to a height of 15.0 min 100s, how much power is developed?

Solution

Given;

F = 5000 N        s = 15.0m    t = 10.0 s      P = ?

W =FxS =5000N x15.0m =75000 J

P =W/t = 75000J/10s = 7500w

Example 7.5

The power expended in lifting an 825N girder to the top of a building 100 m high is

10.0 hp. How much time is required to raise the girder?

Solution

Given: F = 825 N     d = 10m      P = 10.0 hp

w = Fxd

W =825x10m =8250J

P=10hp =10x7461 =7460

P = w/t

T=w/p =82501/7460w = 1.11 seconds

Example 7.6

The mass of a large steel wrecking ball is 2000 kg. What power is used to raise it to

height of 40.0 m if the work is done in 20.0 s? (g=9.8m/s?)

Solution

Given:

m = 2000 kg d = 40.0m t= 20.0 s g=9.8m/s?) P=?

W =mgh =2000kg x40m x9.8m /s2=784000J

P=W /1=784000/ 20s =39, 200W =39.2Kw

7.3 Energy

Definition: Energy is the ability to do work.

Energy transfer is needed to enable people, computers, machines and other devices to work and to enable processes and changes to occur.

Scientists have learned how to change energy from one form into another to make our lives more comfortable.

7.3.1 Forms (Types) of energy

a) Chemical Energy

Food and fuels like oil, gas, coal and wood, are concentrated stores of chemical energy.

b. Electrical energy

Electrical energy is produced by energy transfers at power stations and in batteries

c. Mechanical energy

Mechanical energy is the sum of potential energy and kinetic energy that is the energy associated with the motion & position of an object.

There are different forms of energy. All forms of energy are grouped into two main categories.

a) Kinetic energy. That's energy of motion.

b) Potential energy. That's energy stored in an object due to its position.

1. Potential Energy

It is the energy stored in an object and is measured by the amount of work done.

Examples of potential energy

a) Stretched rubber band

b) A raised weight

c) A river water at the top of water fall

"d) The stretched bow

Mathematically, it denoted as follows:

Potential energy =mgh    

M=mass of the object in kg       h= height in meters ,      g acceleration due to the gravity

Example 7.7

A body of mass 4kg is lifted from the ground and placed at table 5m high from the ground. Calculate the potential energy stored in the body? (Useg=10m/s).

Solution

M= 4kg; h =5; mg=10m/s'; P.E=?   

P.E = mgh

P.E =4kg x10m /s²x5m

P.E = 200J

      Elastic potential Energy

Another common potential energy is elastic potential energy, sometimes called strain.

The amount of elastic potential energy stored in the spring depends on

a) The force applied

b) The a distance moved

. Elastic Potential energy=1/2FX

F= force in N

X= extension of spring in m

Therefore the elastic potential energy can be obtained as follow:

EPE = 1/2 kx²     where k is spring constant

 

Example 7.8

A force of 100N causes a spring to extend by 40cm. Calculate the energy stored in the spring?

Solution

Given: F=100N      x= 0.4m       EPE = ?

EPE= 1/2x100Nx0.4=  20j

2- Kinetic Energy

Any moving body has kinetic energy (K.E.) and the faster it moves, the more K.E. it has

So that the energy in motion is known as kinetic energy.

Equation of kinetic energy

K.E= 1/2mv²

Example 7.8

A bullet of mass 12g travels at 415m/s. find k.E.

 Solution

Given

M=12g = 0.012kg       v= 415m/s   K.E=?

K.E= 1/2mv²

       = 1/2x0.012x(415)²

7.3.2 Sources of Energy

i) Heat energy: Used for cooking food, warming up, etc.

in) Energy from fuels: Used for running cars, buses, etc.

lil) Electric energy: Used for lighting bulbs and tubes, and to run radio, television and household appliances.

Definition

A source of energy is one which can provide adequate amount of energy in a convenient form over a long period of time.

Types of energy sources

All sources of energy can be categorized into two main parts:

a) Non-renewable sources of energy and

b) Renewable sources of energy.

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