Energy work and power ppt Flashcards
Josh's guide to beating shores
2 kinds of energy
potential kinetic
energy can be expressed in what 3 ways?
mechanical work
heat
chemical
what is the common units of energy? (don’t over think)
SI
KE =
kinetic energy (just to know his abreviations)
what is energy of motion masured as?
kinetic energy
what is the formula for kinetic energy?
KE= 1/2 mv2
m=mass
v= velocity
greater mass or speed equals what?
greater kinetic energy
when measuring KE, if you double the speed you will have ____ times more KE
4
______ is the amt of material or matter contained in an object. give examples
Mass
ex: electrons, protons, meutrons)
_________ is mass times gravity
?= m x g
weight
w= m x g
going off the last 2 slides definitions that, mass is the amt of material contained in an object (elcectrons, protons, neutrons), and weight is mass times gravity.
how is this applied if you put mass into space???
you have the same mass in space but a much lighter weight ( much less gravitational pull)
basically remember Mass DOES NOT equal weight!!!
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in the equation for KE which has more of an influance on KE
mass or velocity?
velocity
what is kinetic energy
movement
what is potential energy?
the potential for movement
everything around us has KE, so the more movement the more what?
KE
a pen held in my hand stil is what type of energy?
when i drop it what type of energy is it?
potential
kinetic
what is the energy available or waiting to be converted into power?
potential energy
(PE)
formula for PE
PE= mgh
m= mass
g= gravity
h= change in height
does a glass of water sitting on a table have any energy?
yes!
KE- is part of the internal energy
PE- is the attractive forces associated with PE
what is a form of potential energy in our bodies???
(this his his example from his lecture, not just my random choice, if you disagree and say there are many go listen to his podcast the try again)
ATP
application of KE and PE
Indpiration requires ________energy.
first the _______ energy in chmical ATP is converted to mechanical work, during this process heat will be generated and lost from the system
at teh end of inspiration the elevated rib cage and elastic properties of the lungs have stored ______ energy and drive passive expiration
- KE
- PE
- PE
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what is the basic unit of energy?
Joule
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what is a joule?
the force of one newton that moves it’s point of application
1 meter in the direction of that force!!
what is the expenditure of energy?
work
definition of work
application where force is applied to produce movement in the direction of that force
simple terms= force exerted over a distance
or force acting through distance
formula for work
W= F x D
W= work
F= force
D= distance
if someone is sitting at a desk are the doing the act of work?
no, b/c there is no distance
what units of SI does work use
joules
(might see ergs)
how much work is done pushing on a 100 kg pt on a 75kg operating table and you can’t get teh damn thing to move?
0
no movemnet no work
what is power?
the rate os working or the rate of expending energy
what is power measured in?
watts
what is a watt
1 joule per second
energy may take many forms what are 5 forms
PE
KE
mechanical
chemical
heat
formula for watts
W = Js-1
