Robert Cinca - Physics
Equation
Equation of
of the
the trend
trend line
line (as
(as seen
seen in
in Figure
Figure 6)
6) with
with its
its uncertainties:
uncertainties:
The
The equation
equation that
that has
has resulted
resulted from
from the
the graph
graph is:
is: S=
S= (6.3±
(6.3± 1.8)
1.8) I I - - (0.25
(0.25 ±
± 0.19)
0.19) where:
where:
o
o the
the gradient
gradient =
= 6.3
6.3 ±1.8
±1.8
o
o uncertainty
uncertainty in
in gradient,
gradient,
Dm=(8.4-4.8)/2=1.8
Dm=(8.4-4.8)/2=1.8
o
o y
y intercept
intercept =
= -0.25A
-0.25A ±
± 0.19A
0.19A
o
o uncertainty
uncertainty in
in y
y intercept,
intercept,
Dc=
Dc= (-0.07+0.44)/2=0.19A
(-0.07+0.44)/2=0.19A
Analysis:
Analysis:
Physically,
Physically, this
this means
means that
that the
the size
size of
of the
the maximum
maximum surge
surge current
current is
is significantly
significantly
larger
than
the
final
steady
current.
This
explains
why
filament
bulbs
larger than the final steady current. This explains why filament bulbs sometimes
sometimes blow
blow
when
first
turned
on.
The
large
current
created
damages
the
tungsten
over
time
until
when first turned on. The large current created damages the tungsten over time until
it it finally
finally stops
stops functioning.
functioning.
My
My line
line of
of best
best fit
fit does
does not
not suggest
suggest proportionality,
proportionality, even
even with
with its
its uncertainties,
uncertainties,
however,
my
results
still
give
a
good
impression
on
the
order
of
magnitude
however, my results still give a good impression on the order of magnitude of
of the
the
maximum
surge
current,
when
compared
to
the
final
steady
current.
The
large
maximum surge current, when compared to the final steady current. The large
uncertainties
uncertainties indicate
indicate that
that the
the maximum
maximum surge
surge current
current occurs
occurs in
in such
such a
a small
small time
time
interval
that
even
1000
readings
per
second
is
not
precise
enough
to
record
it.
interval that even 1000 readings per second is not precise enough to record it.
Tertiary
Tertiary relationship:
relationship: the
the time
time taken
taken to
to reach
reach the
the maximum
maximum surge
surge current
current
As
As can
can be
be seen
seen from
from my
my results
results (below),
(below), the
the time
time taken
taken to
to reach
reach the
the maximum
maximum surge
surge
current
is
constant
between
about
0.004
and
0.005
seconds.
My
model
(which
current is constant between about 0.004 and 0.005 seconds. My model (which I I shall
shall
discuss
in
Part
3),
indicated
that
the
maximum
surge
current
occurred
almost
discuss in Part 3), indicated that the maximum surge current occurred almost
instantaneously.
instantaneously.
Time Taken to Reach Maximum Surge Current After Filament Bulb is Turned On, t/s
Time Taken to Reach Maximum Surge Current After Filament Bulb is Turned On, t/s
±0.001s
±0.001s
Average
Uncertainty
Average
Uncertainty
1
2
3
4
5
1
2
3
4
5
0.004
0.005
0.004
0.005
0.005
0.005
0.001
0.004
0.005
0.004
0.005
0.005
0.005
0.001
0.004
0.004
0.004
0.004
0.004
0.004
0.001
0.004
0.004
0.004
0.004
0.004
0.004
0.001
0.005
0.004
0.004
0.004
0.004
0.004
0.001
0.005
0.004
0.004
0.004
0.004
0.004
0.001
0.004
0.004
0.005
0.004
0.004
0.004
0.001
0.004
0.004
0.005
0.004
0.004
0.004
0.001
0.004
0.005
0.004
0.006
0.005
0.005
0.001
0.004
0.005
0.004
0.006
0.005
0.005
0.001
0.008
0.005
0.004
0.005
0.005
0.005
0.002
0.008
0.005
0.004
0.005
0.005
0.005
0.002
0.005
0.004
0.004
0.004
0.005
0.004
0.001
0.005
0.004
0.004
0.004
0.005
0.004
0.001
0.004
0.004
0.004
0.005
0.004
0.004
0.001
0.004
0.004
0.004
0.005
0.004
0.004
0.001
0.008
0.004
0.005
0.004
0.006
0.005
0.002
0.008
0.004
0.005
0.004
0.006
0.005
0.002
0.004
0.003
0.004
0.005
0.004
0.004
0.001
0.004
0.003
0.004
0.005
0.004
0.004
0.001
0.005
0.006
0.005
0.004
0.005
0.005
0.001
0.005
0.006
0.005
0.004
0.005
0.005
0.001
0.005
0.005
0.004
0.006
0.004
0.005
0.001
0.005
0.005
0.004
0.006
0.004
0.005
0.001
Figure 7: Data Table for Tertiary Relationship
Figure 7: Data Table for Tertiary Relationship
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