
41-1
Although we have no control over its passage, we can measure time with more resolution and less uncer-
tainty
th
an
an
y
ot
her
ph
ysical
qu
antity
. e ba
se
un
it
of ti
me,
th
e
se
cond
(s
),
is on
e
of th
e
se
ven
ba
se
un
its
of th
e
In
ternational
Sy
stem
of Un
its
(S
I)
an
d
ca
n
be me
asured
so ac
curately
th
at
nu
merous
ot
her
un
its,
i
ncluding
t
he
m
eter
a
nd
a
mpere,
d
epend
u
pon
i
ts
d
enition
.
Ti
me
me
asurements
ca
n
be di
vided
in
to
two gen
eral
ca
tegories:
ti
me interval
me
asurements
an
d
time synchronization measurements. Time interval measurements determine the duration or elapsed
time between two events. Time standards typically produce 1 pulse per second