newton’s laws of motion. motion and speed vocabulary words motion position reference point ...
TRANSCRIPT
Newton’s Laws of
Motion
Motion and Speed
Voca
bula
ry
Word
s
Motion Position Reference point Distance Displacement Speed Average speed Velocity* Copy down words; define
them for homework!
Act
ivit
ies
NJ Ask Coach Lesson 6 P48-52 Discussion question and
#1-4
Moti
on
The process of changing from one position to another
Speed
How fast an object changes position
Speed= Distance/Time
Calc
ula
ting
Speed
Julie ran from her house on Ridge Road
to Lincoln School; which is 2 miles away.
It took her 20 minutes
to get there; what was
her speed in miles per
minute? 2 miles/20minutes=0.1m/min
Velo
city
Describes an object’s
speed AND its direction
Forces and Motion
Voca
bula
ry
Force gravity newton net force Balanced forces Unbalanced forces Acceleration Friction Air resistance Mass Momentum
Act
ivit
ies
NJ Ask Coach Lesson 7 P. 52-54 Discussion question and
#1-4
Forc
es
A force is a push or a
pull Measured in newtons
Gra
vity The force that exists
between two objects
that have mass, attracting them together
What
is F
rict
ion?
Static Sliding Rolling Fluid A fluid is any matter in
which the molecules
can move freely i.e. air,
water, etc.
Four
Types
of
Fric
tion
The force that occurs
when two objects rub
together
Gra
vity Force that exists
between any two objects that have mass
Gra
vitatio
nal
Rela
tionsh
ips
Free F
all
Free fall- the motion of
a falling object when
the only force acting
on it is gravity In free fall, the force of
gravity is an unbalanced force, which causes an object to accelerate
Free Fa
ll all objects
in free fall
accelerate
at the
same rate
regardless
of their
masses!
Weig
ht
Mass- the amount of
matter in an object Weight- measure of
the force of gravity acting on an object Weight=mass x
acceleration Gravity on Earth is 9.8m/sec2
Calc
ula
ting
Weig
ht Example: Calculate the mass of
an object weighing 10kg:
10kg x 9.8m/s2
Mom
entu
m A property that a
moving object has because of its mass and velocity Momentum = Mass x Velocity
Calc
ula
ting
Mom
entu
m
What is the momentum of a 5kg
bowling ball rolling down a lane at a velocity of 7m/s?=5kg x 7 m/s=35kg x m/s
Law
of
Conse
rvati
on
of
Mom
entu
m The total amount of
momentum in a group
of interacting objects
does not change unless outside forces
act on the objects
New
ton’s
Law
s of
Moti
on
Isaac Newton not only studied
Physics, but was the inventor of
Calculus and one of History’s
most famous scientists
New
ton’s
1st L
aw
of
Moti
on
An object at rest will
stay at rest, and an object in motion will
continue to move in the same direction and the same speed
unless acted upon by
a force. “
1st La
w E
xam
ple
What are some examples of
forces that might stop the
object from moving? To make it
move?
Inert
ia The tendency of a still
or moving object to resist changes in motion
New
ton’s
Seco
nd
Law
of
Moti
on
An object acted on by
a net force will accelerate in the direction of the force.
The object’s acceleration equals the net force divided
by the mass. Acceleration= Force/mass
Force= mass x acceleration
2nd La
w
Exa
mple
A grocery
cart that
weighs 30
kg with a net
force of 60N
acting on it
will
accelerate
at 2 m/s2
because …
acceleration=
force/mass
60N/30kg= 2 m/s2
New
ton’s
Thir
d
Law
of
Moti
on For every action force
exerted on an object,
the object will exert an
equal and opposite reaction.
3rd La
w E
xam
ple
When you
are
swimming
and you pull
your arms
through the
water in one
direction,
your body
moves in
the opposite
direction
Energy
Energy, Work, Power and
Heat
Voca
bula
ry
Work Joule Energy Kinetic energy Potential energy Power
Act
ivit
ies
NJ Ask Coach Lesson 8 P.55-59 Discussion question and
#1-4
Work
Work- result of a force
moving an object over
a distance The unit of measurement for work
is a joule Work= Force x Distance
Pote
ntia
l vs.
Kin
etic E
nerg
y
Potential EnergyKinetic Energy
Pow
er Power is the amount
of work done in a period of time Power= Work/Time
Remember: work is
measured in joules and
time is measured in seconds
Energ
y
Energy- the ability to
do work or cause change Kinetic energy- the
energy an object has
because it is moving Potential energy-
stored energy
Therm
al E
nerg
y Thermal energy, or
heat, is the total energy of the movement of molecules in a
substance
Heat
Transf
er
There are three ways
heat can be transferred: Convection Conduction Radiation Radiation is the transfer of energy via
electromagnetic waves
Conductio
n Conductio
n is a
situation
where the
heat
source and
heat sink
are
connected
by matter.
Tem
pera
ture
vs.
Heat
Temperature
Temperatur
e is a
measure of
the average
kinetic
energy
level of a
substance
Heat
Heat is the
total
energy
associated
with the
motion of
molecules
Measu
ring
Tem
pera
ture
Temperatu
re can be
measured
in…
Fahrenheit
Celsius
Kelvin
Fahre
nheit
Fahrenheit is the classic English system
of measuring temperatures. Water freezes at 32
degrees Fahrenheit Water boils at 212
degrees
Cels
ius
Celsius is the modern
system of measuring
temperature. The freezing point of
water is 0 degrees Celsius the boiling point is
100 degrees Celsius
Form
ula
Celsius=(Fahrenheit Temperature -32)*5/9
Therm
al
Exp
ansi
on
Thermal expansion
is when gases expand
as the temperature increases Think about it… Have you ever been hot
and sticky and felt that
your clothes seemed
tighter or that your hand were swelling? This is an example of
thermal expansion
Contr
act
ion
The opposite of expansion is contraction A substance will
contract when heat is
removed If you remove enough
heat from a gas it will
become a liquid Liquids can turn into
solids with further cooling
The E
nd!!