A
longitudinal
wave
is
a
wave
which
travels
in
a
direction
____________________
to
the
direction
of
vibrations
.
An
example
of
a
longitudinal
wave
is
____________________
.
This
is
an
example
of
how
sound
is
produced
from
a
loudspeaker
:
The
loudspeaker
____________________
,
making
air
molecules
surrounding
it
____________________
and
therefore
transferring
vibration
and
____________________
to
other
molecules
.
This
will
produce
a
____________________
wave
which
is
made
up
of
series
of
____________________
and
____________________
.
Here
is
another
example
of
how
sound
is
produced
from
a
guitar
:
The
guitar's
string
____________________
,
making
____________________
____________________
surrounding
it
____________________
and
therefore
____________________
____________________
and
____________________
to
____________________
____________________
.
This
will
produce
a
____________________
wave
which
is
made
up
of
series
of
____________________
and
____________________
.
Compression
is
a
region
where
air
molecules
are
____________________
together
and
they
have
____________________
pressure
.
Rarefaction
,
on
the
other
hand
,
is
a
region
where
____________________
____________________
are
____________________
____________________
and
they
have
____________________
pressure
.
