AP-2ND SE C2 V3
7
A i Ph i 160 Chapter 2 Physics in Action Physics Words Newton’s second law of motion: the acceleration of an object is directly proportional to the unbalanced force acting on it and inversely proportional to the object’s mass. The direction of the acceleration is the same as the direction of the unbalanced force. NEWTON’S SECOND LAW OF MOTION Evidence for Newton’s Second Law of Motion In the Investigate, you observed that it was difficult to push on an object with a constant force because the object would move faster and faster. This observation that a constant force produces an acceleration is very important in physics. You also found that if you pushed on a more massive object with the same force, it did not accelerate as much. This observation that the acceleration decreases with an increase in mass is also very important. Based on observations from investigations similar to yours, Isaac Newton wrote his (Newton’s) second law of motion: The acceleration of an object is directly proportional to the unbalanced force acting on it and is inversely proportional to the object’s mass. The direction of the acceleration is the same as the direction of the unbalanced force. You saw the evidence for Newton’s second law in the Investigate. When you pushed an object with a small force, the object had a small acceleration. The speed of the object increased, but not very quickly. When you pushed the object with a large force the object had a large acceleration. Newton’s second law states this: “The acceleration of an object is directly proportional to the unbalanced force acting on it.” This is a mathematical way of saying that the larger force produces a larger acceleration. As the force gets larger, the acceleration gets larger — a direct proportion. In this Investigate, the force was a push. You also found that the same force on a small mass produced a larger acceleration than it did on a large mass. Newton’s second law states this, “The acceleration of an object is… inversely proportional to the object’s mass.” This is a mathematical way of saying that the larger the mass, the smaller the acceleration. As the mass gets larger, the acceleration gets smaller — an inverse proportion. To achieve a big acceleration, you need to apply a large force to a small mass. In one of the most important science books of all time, Principia, Isaac Newton wrote his second law of motion. It is interesting both historically and in terms of understanding physics to read Newton’s second law in his own words: “The change in motion is proportional to the motive force impressed; and is made in the direction of the right line in which that force is impressed.” Physics Talk
Transcript of AP-2ND SE C2 V3
A i Ph i160
Chapter 2 Physics in Action
Physics WordsNewton’s second law of motion: the acceleration of an object is directly proportional to the unbalanced force acting on it and inversely proportional to the object’s mass. The direction of the acceleration is the same as the direction of the unbalanced force.
NEWTON’S SECOND LAW OF MOTIONEvidence for Newton’s Second Law of Motion
In the Investigate, you observed that it was difficult to push on an object with a constant force because the object would move faster and faster. This observation that a constant force produces an acceleration is very important in physics.
You also found that if you pushed on a more massive object with the same force, it did not accelerate as much. This observation that the acceleration decreases with an increase in mass is also very important.
Based on observations from investigations similar to yours, Isaac Newton wrote his (Newton’s) second law of motion: The acceleration of an object is directly proportional to the unbalanced force acting on it and is inversely proportional to the object’s mass. The direction of the acceleration is the same as the direction of the unbalanced force.
You saw the evidence for Newton’s second law in the Investigate. When you pushed an object with a small force, the object had a small acceleration. The speed of the object increased, but not very quickly. When you pushed the object with a large force the object had a large acceleration. Newton’s second law states this: “The acceleration of an object is directly proportional to the unbalanced force acting on it.” This is a mathematical way of saying that the larger force produces a larger acceleration. As the force gets larger, the acceleration gets larger — a direct proportion. In this Investigate, the force was a push.
You also found that the same force on a small mass produced a larger acceleration than it did on a large mass. Newton’s second law states this, “The acceleration of an object is… inversely proportional to the object’s mass.” This is a mathematical way of saying that the larger the mass, the smaller the acceleration. As the mass gets larger, the acceleration gets smaller — an inverse proportion. To achieve a big acceleration, you need to apply a large force to a small mass.
In one of the most important science books of all time, Principia, Isaac Newton wrote his second law of motion. It is interesting both historically and in terms of understanding physics to read Newton’s second law in his own words:
“The change in motion is proportional to the motive force impressed; and is made in the direction of the right line in which that force is impressed.”
Physics Talk
165
Sec
tion
3 N
ewto
n’s
Seco
nd L
Det
erm
inin
g t
he
Nu
mb
er o
f Si
gn
ific
ant
Fig
ure
s in
a M
easu
rem
ent
Ther
e ar
e g
uid
elin
es t
hat
yo
u c
an u
se t
o d
eter
min
e th
e n
um
ber
o
f si
gn
ific
ant
fig
ure
s in
a m
easu
rem
ent.
All
no
nze
ro n
um
ber
s ar
e co
nsi
der
ed t
o b
e si
gn
ific
ant
fig
ure
s.
In t
he
mea
sure
men
t 15
2.5
m, a
ll th
e d
igit
s ar
e si
gn
ific
ant.
Th
e m
easu
rem
ent
has
fo
ur
sig
nif
ican
t fi
gu
res.
Zero
s m
ay o
r m
ay n
ot
be
sig
nif
ican
t, d
epen
din
g o
n t
hei
r p
lace
in
a n
um
ber
.
• A
zer
o b
etw
een
no
nze
ro d
igit
s is
a s
ign
ific
ant
fig
ure
. In
th
e m
easu
rem
ent
308
g, t
he
zero
is s
ign
ific
ant.
Th
e m
easu
rem
ent
has
th
ree
sig
nif
ican
t fi
gu
res.
• A
zer
o a
t th
e en
d o
f a
dec
imal
nu
mb
er is
co
nsi
der
ed s
ign
ific
ant.
In
th
e m
easu
rem
ent
1.50
N, t
he
zero
is s
ign
ific
ant.
Th
e m
easu
rem
ent
has
th
ree
sig
nif
ican
t fi
gu
res.
• A
zer
o a
t th
e b
egin
nin
g o
f a
dec
imal
nu
mb
er is
no
t si
gn
ific
ant.
In
th
e m
easu
rem
ent
0.02
3 kg
, th
e ze
ros
are
no
t si
gn
ific
ant.
Th
e m
easu
rem
ent
has
tw
o s
ign
ific
ant
fig
ure
s.
• In
a la
rge
nu
mb
er w
ith
ou
t a
dec
imal
po
int,
th
e ze
ros
are
no
t si
gn
ific
ant.
In t
he
mea
sure
men
t 20
00 k
g, t
he
zero
s ar
e n
ot
sig
nif
ican
t. T
he
mea
sure
men
t h
as o
ne
sig
nif
ican
t fi
gu
re.
Ho
wev
er, i
f th
e ze
ros
in 2
000
wer
e si
gn
ific
ant,
it w
ou
ld b
e w
ritt
en a
s 20
00. o
r in
exp
on
enti
al n
ota
tio
n a
s 2.
000
× 1
03 .
Sig
nif
ican
t Fi
gu
res
in C
alcu
lati
on
s
Ther
e ar
e al
so g
uid
elin
es t
hat
yo
u c
an u
se w
hen
mak
ing
yo
ur
calc
ula
tio
ns.
Ad
din
g a
nd
Su
btr
acti
ng
Wh
en a
dd
ing
or
sub
trac
tin
g,
the
fin
al r
esu
lt s
ho
uld
hav
e th
e sa
me
nu
mb
er o
f d
ecim
al p
lace
s as
th
e m
easu
rem
ent
wit
h t
he
few
est
dec
imal
pla
ces.
Mu
ltip
lyin
g a
nd
Div
idin
g
Wh
en m
ult
iply
ing
or
div
idin
g,
the
resu
lt s
ho
uld
hav
e n
o m
ore
si
gn
ific
ant
dig
its
than
th
e fa
cto
r h
avin
g t
he
few
est
nu
mb
er
of
sig
nif
ican
t d
igit
s.
AP
_3rd
Ed_
SE
_C2.
indd
S
ec1:
165
7/29
/10
12:
57:3
2 P
M
![Jan Beutel, ETH Zurich - Welcome - TIK...[B. Jelk] High‐resolution TimelapsePhotography 2009 C2 2010 C2 2011 C2 2012 C2 2013 C2 2014 C2 18.05.2015 C2 19.05.2015 C2 29.05.2015 C2](https://static.fdocuments.us/doc/165x107/60110b99540db573571546c3/jan-beutel-eth-zurich-welcome-tik-b-jelk-higharesolution-timelapsephotography.jpg)
![INNOVATIONS - AD Kulan · Berlingo [M49.M59] C15 C-Crosser [EP.I4] Cl [BO] C1 [2] C2[A6] СЗ [A8.A31] C3-Pluriel [A42] C4 Aircross C5 [DC] C5 Break [DEI C8 [V3] C8[V3] Evasion [U60]](https://static.fdocuments.us/doc/165x107/614ad62512c9616cbc69ac6f/innovations-ad-kulan-berlingo-m49m59-c15-c-crosser-epi4-cl-bo-c1-2-c2a6.jpg)