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Lesson
Three‐Newton’s
Second
Law
Name___________________________________
Date__________________
Newton’s
Second
Law
1.
The
presence
of
an
unbalanced
force
will
accelerate
an
object
by
__changing
speed____,
_____changing
direction_________,
or
by
changing
both.
2.
The
application
of
balanced
forces
means
that
the
motion
of
an
object
remains
the
same.
(true,
false)
3.
Newton's
second
law
of
motion
pertains
to
the
behavior
of
objects
for
which
all
existing
forces
are
______not
balanced________
4.
The
acceleration
of
an
object
depends
on
_____the
size
of
the
force______
and
______the
mass
of
the
object___________
5.
State
Newton’s
Second
Law
of
Motion.
The
acceleration
of
an
object
as
produced
by
a
net
force
is
directly
proportional
to
the
magnitude
of
the
net
force,
in
the
same
direction
as
the
net
force,
and
inversely
proportional
to
the
mass
of
the
object.
6.
The
most
familiar
statement
of
Newton’s
Second
Law
in
equation
form
is
____F
=
ma__________
7.
The
unit
of
force
is
______Newton___________
8.
Complete
the
following
table:
Example
Net
Force
(N)
mass
(kg)
Acceleration
(m/s/s)
1.
100
10
10
2.
72
20
3.6
3.
75
25
3.0
4.
64
3.2
20
5.
69
15
4.6
6.
80
33.3
2.4
9.
What
is
the
magnitude
and
direction
of
the
net
force
for
each
example?
Write
answer
inside
box.
a.
10 N
10 N
0N
c.
10 N
e.
17 N
b.
d.
7N left
3N
12 N
5N left
10.
Read
The
Big
Misconception
f.
12 N
12 N
12 N
0N
12N right
6N left
12 N
24 N
6N
Finding
Acceleration
11.
If
each
of
the
boxes
in
the
previous
question
had
a
mass
of
5
kg,
what
would
be
the
acceleration
and
direction
of
motion
for
each?
Use
the
terms
right
or
left
for
direction.
a._____0____
b.
____0_____
d.___2.4
m/s/s
right___
e.__1.0
m/s/s
right___
c.___1.4
m/s/s
left______
f.____1.2
m/s/s
left__
Free
Fall
and
Air
Resistance
12.
During
free
fall,
all
objects
will
fall
with
the
same
rate
of
___acceleration____
13.
During
free
fall
,
the
force
of
gravity
on
any
mass
is
the
same.
(true,
false)
14.
During
free
fall,
a
greater
force
is
required
to
accelerate
a
greater
mass.
(true,
false)
15.
During
free
fall,
the
ratio
of
net
force
to
mass
is
(less
for
less
massive
objects,
the
same
for
all
objects,
more
for
more
massive
objects)
16.
Air
resistance
is
the
result
of
collisions
of
the
object’s
leading
surface
with
air
molecules
17.
For
our
discussion,
the
two
most
common
factors
on
which
air
resistance
depends
are
______speed_________and______cross‐sectional
area_________
18.
What
is
the
net
force
on
an
object
falling
at
terminal
velocity?
_________zero
_______________
19.
At
terminal
velocity,
what
is
the
relationship
between
the
force
of
gravity
on
the
object
and
the
force
exerted
by
air
resistance?
_________They
are
equal________________________
20.
If
air
resistance
is
present,
more
massive
objects
of
the
same
size
and
shape
fall
(more
slowly
than,
at
the
same
rate
as,
more
quickly
than)
their
less
massive
counterparts.
Lesson
Four‐Newton’s
Third
Law
21.
State
Newton’s
Third
Law
For
evry
action,
there
is
an
equal
and
opposite
reaction
22.
What
does
the
statement
“Forces
always
come
in
pairs”
mean?
A
force
cannot
be
applied
to
an
object
without
the
object
applying
a
force
back
23.
What
is
the
reaction
force
to
the
forces
named:
Action
Force
Reaction
Force
Walking,
you
push
ground
backwards
Ground
pushes
you
forward
A
bat
hits
a
baseball
Ball
hits
a
bat
I
push
against
a
wall
Wall
pushes
against
me
A
bird
pushes
air
downward
Air
pushes
bird
upward
A
car’s
wheels
push
road
backwards
Road
pushes
car
wheels
forward