Ex Mensura, Scientia

High-precision height calculator. Companion to Wndsn Telemeters: Low tech, high utility graphical distance & altitude computers from the Wndsn applied science lab.

*By way of using a Wndsn Quadrant or Telemeter measuring degrees or a hairline graticule measuring mil or moa or any other instrument or technique that returns the angular size of a known object, we can determine the height of that object.*

- Distance to the object observed:
`d = 4.5`

- Angular size:
`α = 2 degrees`

or`34.91 MIL`

(MRAD) or`35.56 MIL`

(NATO-MIL) or`120 MOA`

- Height multiplier
`tan(2°)`

:`s = d · 0.03`

**Approximate height:**`s = 0.16`

The *display* precision set is `.2`

. To change that, edit the variable `&digits=x`

in the URL where `0 <= x <= 9`

.

[Load sample values (JSON) (XML) (CSV).]

Compare MIL vs. MRAD vs. NATO-MIL.

`s = d · tan(α)`

`s = 4.5 · tan(2°)`

**s = 0.16**- (We have one angle (2°) and the Adjacent side (4.5), and want to determine the Opposite side. According to SOHCAHTOA, we need to use Tangent.)
- (The small angle approximation for skinny triangles shows that the angle in radians approximates to the sine of the angle (for small angles, the hypotenuse is
*about*equal to the adjacent); hence, the larger the angle, the bigger the difference between sin(α) and tan(α).)