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.
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.
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:
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."
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.
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.
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.
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.
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.