Closed system a systemwhere the net energychange is 0
work done energytransferred when a force moves an objectthrough a distance
dissipated wasted
friction caused energy to be transferred to thermal
lubricants can reduce friction
Power rate ofenergywansye how much energy is transferred
powerfulmachine wansyesalot ofenergy in a short spaceof time
force a push pull on an object that is caused by it interacting with somethin
contactforce when 2 objects have to be touchingyou a force to act
friction air resistance tension in ropes normal contact yo ice
non contact when objects dont need to be touchingyou the force to act
force
interaction pair a pair offorces that are equal and opposite and act on 2
interacting objects sametypeofforce
freebodyforce diagrams
shows an forcesacting on system but not ones system exerts
forces represented by arrows lengths snow reran've magnitude
show if there is a resultant force singleforce which has some eject as
an o o forces
normal contact force
resist c thrust
A
weight
if forcessetana act
along a
direction as
line add them together to find resultant
force being negative
scale drawings
jor when forces arent acting in one line
to
draw an forces tip tail to scare right direction
draw a straight line from the start offirstforce to the end of the last this
is the resultant force length magnitude bearing direction
FBI
so
SD y
34 resultant force SN
in 3 suits an on bearing
of 037
,balanced forces
on SD if the tipof the lastforce meets the tail of the istjuice the forces are
balanced and its in equilibrium
resolvingforces
splittingan angledforce into 2 components
moments
turning eject a force
distance of
normal to air echon distance between where the force is
of force
a line that makes a
applied and the pivot along right angle with the direction
offorce
overall moment difference between sun of clockwise moments and sun
of anticlockwisemoments
principle of moments jor any object in equilibrium
sum
of clockwise moments sum of ann clockwise moments
centre a singlepoint that the whole mass is concentrate
of mass at
you assume
levers transmit the
tuning effectof a force making it easier for us to do
work
increase distance
from pivot and force sman yore creates large
moment which is equal to the moment created on the other side of the
pivot
gears circular discs with teeth around their edges
teeth interlock so that tuning one causes another to turn in theopposite
direction
used to transmit the rotational effect a forcefrom one place to another
of
2 adjacent interlockinggears wie spin in oppositedirections
largegears wie spinslower
, g g p s
electricity and circuits
fi cell
ft ft battery o switch
A ammeter V voltmeter M motor
resistor thermistor variable resistor
juse
DT diode DELED EDT LDR
X jilimentlamp 0 to do supply o o ac supply
current flowsfrompositive terminals to negativeterminals
voltmeter measures p d
connected in parallel across a component
ammeter measures current
connected in series in line with a component
current the rate ofglow ofcharge
p d voltage the drivingforce that pushes chargearound
charge win onlyglowifthere is a p d
usuallyprovidedby cell battery
pa the unit
energy transferred per charged passed
resistance anything in the circuit which reduces the flow of current
in most cases temp of componentT resistance T
if
A pg 224
thermistors a resistor thats resistance depends on its temp
resistancedecreaseswhen temp increases
LDR a resistor thats resistance depends
resistance decreases when
of lightintensity
light increases
investigatingresistance og
thermistors I placethermistor in a waterbath and add enough water to cover it
2 record temp
of water with thermometer
3 measure current through circuit
youevey 5 increase
4 Keep p a constant
S R V1 I
LDRs 1 in a darkened room shine a torch on the LDR at a mown distance
2 gradually move the torch awayfromthe LDK
3 record the currentyouevery10cm
work done energytransferred when a force moves an objectthrough a distance
dissipated wasted
friction caused energy to be transferred to thermal
lubricants can reduce friction
Power rate ofenergywansye how much energy is transferred
powerfulmachine wansyesalot ofenergy in a short spaceof time
force a push pull on an object that is caused by it interacting with somethin
contactforce when 2 objects have to be touchingyou a force to act
friction air resistance tension in ropes normal contact yo ice
non contact when objects dont need to be touchingyou the force to act
force
interaction pair a pair offorces that are equal and opposite and act on 2
interacting objects sametypeofforce
freebodyforce diagrams
shows an forcesacting on system but not ones system exerts
forces represented by arrows lengths snow reran've magnitude
show if there is a resultant force singleforce which has some eject as
an o o forces
normal contact force
resist c thrust
A
weight
if forcessetana act
along a
direction as
line add them together to find resultant
force being negative
scale drawings
jor when forces arent acting in one line
to
draw an forces tip tail to scare right direction
draw a straight line from the start offirstforce to the end of the last this
is the resultant force length magnitude bearing direction
FBI
so
SD y
34 resultant force SN
in 3 suits an on bearing
of 037
,balanced forces
on SD if the tipof the lastforce meets the tail of the istjuice the forces are
balanced and its in equilibrium
resolvingforces
splittingan angledforce into 2 components
moments
turning eject a force
distance of
normal to air echon distance between where the force is
of force
a line that makes a
applied and the pivot along right angle with the direction
offorce
overall moment difference between sun of clockwise moments and sun
of anticlockwisemoments
principle of moments jor any object in equilibrium
sum
of clockwise moments sum of ann clockwise moments
centre a singlepoint that the whole mass is concentrate
of mass at
you assume
levers transmit the
tuning effectof a force making it easier for us to do
work
increase distance
from pivot and force sman yore creates large
moment which is equal to the moment created on the other side of the
pivot
gears circular discs with teeth around their edges
teeth interlock so that tuning one causes another to turn in theopposite
direction
used to transmit the rotational effect a forcefrom one place to another
of
2 adjacent interlockinggears wie spin in oppositedirections
largegears wie spinslower
, g g p s
electricity and circuits
fi cell
ft ft battery o switch
A ammeter V voltmeter M motor
resistor thermistor variable resistor
juse
DT diode DELED EDT LDR
X jilimentlamp 0 to do supply o o ac supply
current flowsfrompositive terminals to negativeterminals
voltmeter measures p d
connected in parallel across a component
ammeter measures current
connected in series in line with a component
current the rate ofglow ofcharge
p d voltage the drivingforce that pushes chargearound
charge win onlyglowifthere is a p d
usuallyprovidedby cell battery
pa the unit
energy transferred per charged passed
resistance anything in the circuit which reduces the flow of current
in most cases temp of componentT resistance T
if
A pg 224
thermistors a resistor thats resistance depends on its temp
resistancedecreaseswhen temp increases
LDR a resistor thats resistance depends
resistance decreases when
of lightintensity
light increases
investigatingresistance og
thermistors I placethermistor in a waterbath and add enough water to cover it
2 record temp
of water with thermometer
3 measure current through circuit
youevey 5 increase
4 Keep p a constant
S R V1 I
LDRs 1 in a darkened room shine a torch on the LDR at a mown distance
2 gradually move the torch awayfromthe LDK
3 record the currentyouevery10cm
