Summary Grade 12 IEB Physical Science - Work, Energy, and Power
7 views 0 purchase
Course
Physical Sciences
Institution
12th Grade
This Grade 12 IEB Physical Science guide on work, energy, and power covers essential physics concepts, including kinetic and potential energy, the work-energy theorem, and power calculations. It explains energy conservation and efficiency with practical examples, making it perfect for students prep...
The principle of conservation of Em Power Efficiency
X ENER O · definition : In the absence of air resistence or
any external definition :
efficiency is the rat of output power
forces ,
the mechanical
energy (Em) of an object is constant
to input power
En Epi Eki Epf Epf
+
symbols
+
very view devices can transfer form
=
energy from
:
·
in · one
· external forces include :
friction , applied forces and normal forces .
into another without wasting some on the way
k
done on an object :
·
Also note : Emech bottom
=
Emech top ·
using efficiency
calculated : =
power out X 100
· definition The :
product of the displacement otsupp-Ediss Demeen
The theorem
+
power in
work-energy
:
and the component of the force parallel to
a net force
↳ dissapated (lost)
the displacement
·
gives relationship between the work done by
and the change in Kinetic
energy (Emech
·
equation : W =
FAX (J) -
scalar A =
Ep)
States
· :
the work done on an object by a net force is equal
· When work is done , energy Is transfered +
ep
to the change in kinetic energy of the object Ek
ve
and negative work :
Emech
=
· In symbols :
Fret Ax =
DEK
has force
.
· (t) : a in direction of displacement Whet AEK (1)
,
o equation :
=
(Emech-Ek)
energy transfered to object of
law of conservation of
energy
:
B
C) has a force in opposite direction of
:
·
· states : The total energy in a
system cannot be created nor
displacement, energy removed from object
destroyed only transfered from one form to another
S > conservative forces
ie gravitational force
:
does not
(fg)
change mechanical energy of object
&
> f
> Ax
(positive work
Gravitational potential energy (E) non-conservative forces changes the object
< :
mechanical
energy
· definition the :
energy an object possesses due to (negative work)
le
applied forces and tensions
F
its position relative to reference point. DC
Wext Dep + DEK
* >
work done by external forces use
=
· to calculate
equation Ep migh (1)
: =
·
(not on formula sheet) ,
also shown as Next =
EmechA-Emech is
-F
Kinetic energy (EK) which comes from Emecha + Wext =
Emechs
the energy an object possesses dre
so
· definition :
(zero work)
to its motion * > DS
EMV2 + +of
equation (1) x
-
· :
EK =
· definition :
the rate at which work is done
Mechanical
energy (EM) s equation : p = / (W)
·
definition : the sum of
gravitational and kinetic Average power :
energy at a point · the average power required to keep an object at constant speed is
· In Symbols :
Em =
Ep +
EK the product of the applied force (f) and the
average speed (v)
·
at rest EM only made up of Ep only when
is of the object
moving on ground Em made up of Ekonly o equation : P =
Fu (w)
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller TanyaChigs. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $8.45. You're not tied to anything after your purchase.