We are PANTHER Academy students. We have

RecordedData

measured the paral ax angle and directly have

measured the distance for each object and have

recorded the data in a table Then, we graph

the data, plotting paral ax angle as a function

of distance.

We have analyzed the graph and have determined

an approximate functional dependence for paral ax

with distance. Then, based on studying trigonometry,

Distance Paral axAngle

we have plot diagrams of the paral ax measurements;

(ft)

(degree)

and we have used trigonometry to derive what the

actual functional dependence is:

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b=baseline,p=paral axangle,d=distance

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tan(p/2)=(b/2)/d

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p=2tan-1(b/2d)

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We have plot this function on the same graph as

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our data and have compared our measurements

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with the theoretical prediction from geometry.

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We know for this to work properly, the reference

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point used in the paral ax.

Measurements must be far away and exhibit little

paral ax itself. Otherwise, the data wil be

systematical y skewed to lower paral ax values.

One way to do this is to place reference targets

on the far wal of the classroom and space them

apart the Same length as the baseline we are using.

When we are on one side of the baseline, we line

up with the reference target on the same side of the

target object (see figure).

It is important to line up the eye arrow with the

reference object or target object arrow plus the

objects ourselves when making our measurements.

To do this, we kept the angle measurer fixed in

place but move our eye to line up the arrows with

the targets. If we do not move our eye, we wil

get paral ax values systematical y skewed to

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higher values.