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What is this used for? Quiz for pilots ....

Posted: Wed Oct 15, 2008 4:47 pm
by John Young
Hi Guys,

What is this essential piece of equipment used for? :?:

Something that I find indispensable. :idea: :idea:

Before Trikenut shouts "Photo's pleese", here's the photo. vhpy

Regards
John ZU-sEXY

Re: What is this used for? Quiz for pilots ....

Posted: Wed Oct 15, 2008 4:53 pm
by Trikenut
John Young wrote:Before Trikenut shouts "Photo's pleese", here's the photo. vhpy
Ya, ya.. vhpy
I just like to see photos as it shows the thing visually!! :oops:

Re: What is this used for? Quiz for pilots ....

Posted: Wed Oct 15, 2008 5:12 pm
by John Boucher
I've got a problem with 3-D :lol: could you be so kind as to show it at different angles please sir! :shock:

Re: What is this used for? Quiz for pilots ....

Posted: Wed Oct 15, 2008 5:16 pm
by extra300s
All I know is that what ever you do with it, there must be a way better piece of equipment for the job. Nothing flying related I would allso guess :roll: I need more clues! vhpy :?: (**)

Re: What is this used for? Quiz for pilots ....

Posted: Wed Oct 15, 2008 5:17 pm
by John Young
Bad Nav wrote:I've got a problem with 3-D :lol: could you be so kind as to show it at different angles please sir! :shock:
Hi,

Surely - just for you ... !!!!

Regards
John ZY-sEXY

Re: What is this used for? Quiz for pilots ....

Posted: Wed Oct 15, 2008 5:20 pm
by John Young
extra300s wrote:All I know is that what ever you do with it, there must be a way better piece of equipment for the job. Nothing flying related I would allso guess :roll: I need more clues! vhpy :?: (**)
Hi,

Definitely very flying related. :idea:

Regards
John ZU-sEXY

Re: What is this used for? Quiz for pilots ....

Posted: Wed Oct 15, 2008 7:07 pm
by DarkHelmet
It looks like a chock - the same thing I paid R40 for 3 at GAME for 3 yellow blocks - no flipping over, no rolling on the tarmac (have not flown on grass for a while!)

Seriously - WTF?

Re: What is this used for? Quiz for pilots ....

Posted: Wed Oct 15, 2008 7:11 pm
by DarkHelmet
On second thought - them bars look way too thin to hold back a 912S, it is a "wife satisfaction flimsy device"... Look - I park my aerie in this and if it bends I am safe to fly, if it does not bend I stay on the ground!

Re: What is this used for? Quiz for pilots ....

Posted: Wed Oct 15, 2008 7:15 pm
by DarkHelmet
Not all of us fly GT450's - it is your "lift up my babe's nose and walk her to the hangar safely" device

Re: What is this used for? Quiz for pilots ....

Posted: Wed Oct 15, 2008 7:49 pm
by John Young
Hi,

Nah, not a chock, nor a wife satisfier, nor a lifting the baby's nose device .... vhpy

Quack-Mate if he comes and quacks around here will probably work it out. :idea:

Regards
John ZU-sEXY

Re: What is this used for? Quiz for pilots ....

Posted: Wed Oct 15, 2008 8:11 pm
by Uncle Spud Murphy
Tent Frame for the overnighters boet - so it is (^^)

Re: What is this used for? Quiz for pilots ....

Posted: Wed Oct 15, 2008 8:36 pm
by Boet
Is dit dalk n rytoom vir n gans, of dalk n stellasie om vrugte op droog te maak??

Re: What is this used for? Quiz for pilots ....

Posted: Wed Oct 15, 2008 9:10 pm
by Duck Rogers
John Young wrote:Hi,

Nah, not a chock, nor a wife satisfier, nor a lifting the baby's nose device .... vhpy

Quack-Mate if he comes and quacks around here will probably work it out. :idea:

Regards
John ZU-sEXY
Thank you for placing so much trust in my ability to analytically dissect and compute this complex phenomenon.
Herewith the answer to your riddle:


S=\frac{1}{2}bh

where S is area, b is the length of the base of the triangle, and h is the height or altitude of the triangle. The term 'base' denotes any side, and 'height' denotes the length of a perpendicular from the point opposite the side onto the side itself.

Although simple, this formula is only useful if the height can be readily found. For example, the surveyor of a triangular field measures the length of each side, and can find the area from his results without having to construct a 'height'. Various methods may be used in practice, depending on what is known about the triangle. The following is a selection of frequently used formulae for the area of a triangle.[4]

Using vectors

The area of a parallelogram can be calculated using vectors. Let vectors AB and AC point respectively from A to B and from A to C. The area of parallelogram ABDC is then |{AB}\times{AC}|, which is the magnitude of the cross product of vectors AB and AC. |{AB}\times{AC}| is equal to |{h}\times{AC}|, where h represents the altitude h as a vector.

The area of triangle ABC is half of this, or S = \frac{1}{2}|{AB}\times{AC}|.

The area of triangle ABC can also be expressed in terms of dot products as follows:

\frac{1}{2} \sqrt{(\mathbf{AB} \cdot \mathbf{AB})(\mathbf{AC} \cdot \mathbf{AC}) -(\mathbf{AB} \cdot \mathbf{AC})^2} =\frac{1}{2} \sqrt{ |\mathbf{AB}|^2 |\mathbf{AC}|^2 -(\mathbf{AB} \cdot \mathbf{AC})^2} \, .

Applying trigonometry to find the altitude h.
Applying trigonometry to find the altitude h.

Using trigonometry

The height of a triangle can be found through an application of trigonometry. Using the labelling as in the image on the left, the altitude is h = a sin γ. Substituting this in the formula S = ½bh derived above, the area of the triangle can be expressed as:

S = \frac{1}{2}ab\sin \gamma = \frac{1}{2}bc\sin \alpha = \frac{1}{2}ca\sin \beta.

Furthermore, since sin α = sin (π - α) = sin (β + γ), and similarly for the other two angles:

S = \frac{1}{2}ab\sin (\alpha+\beta) = \frac{1}{2}bc\sin (\beta+\gamma) = \frac{1}{2}ca\sin (\gamma+\alpha).

[edit] Using coordinates

If vertex A is located at the origin (0, 0) of a Cartesian coordinate system and the coordinates of the other two vertices are given by B = (xB, yB) and C = (xC, yC), then the area S can be computed as ½ times the absolute value of the determinant

S=\frac{1}{2}\left|\det\begin{pmatrix}x_B & x_C \\ y_B & y_C \end{pmatrix}\right| = \frac{1}{2}|x_B y_C - x_C y_B|.

For three general vertices, the equation is:

S=\frac{1}{2} \left| \det\begin{pmatrix}x_A & x_B & x_C \\ y_A & y_B & y_C \\ 1 & 1 & 1\end{pmatrix} \right| = \frac{1}{2} \big| x_A y_C - x_A y_B + x_B y_A - x_B y_C + x_C y_B - x_C y_A \big|
S= \frac{1}{2} \big| (x_C - x_A) (y_B - y_A) - (x_B - x_A) (y_C - y_A) \big|.

In three dimensions, the area of a general triangle {A = (xA, yA, zA), B = (xB, yB, zB) and C = (xC, yC, zC)} is the Pythagorean sum of the areas of the respective projections on the three principal planes (i.e. x = 0, y = 0 and z = 0):

S=\frac{1}{2} \sqrt{ \left( \det\begin{pmatrix} x_A & x_B & x_C \\ y_A & y_B & y_C \\ 1 & 1 & 1 \end{pmatrix} \right)^2 + \left( \det\begin{pmatrix} y_A & y_B & y_C \\ z_A & z_B & z_C \\ 1 & 1 & 1 \end{pmatrix} \right)^2 + \left( \det\begin{pmatrix} z_A & z_B & z_C \\ x_A & x_B & x_C \\ 1 & 1 & 1 \end{pmatrix} \right)^2 }.

Using Heron's formula

The shape of the triangle is determined by the lengths of the sides alone. Therefore the area S also can be derived from the lengths of the sides. By Heron's formula:

S = \sqrt{s(s-a)(s-b)(s-c)}

where s = ½ (a + b + c) is the semiperimeter, or half of the triangle's perimeter.

Three equivalent ways of writing Heron's formula are

S = \frac{1}{4} \sqrt{(a^2+b^2+c^2)^2-2(a^4+b^4+c^4)}

S = \frac{1}{4} \sqrt{2(a^2b^2+a^2c^2+b^2c^2)-(a^4+b^4+c^4)}

S = \frac{1}{4} \sqrt{(a+b-c) (a-b+c) (-a+b+c) (a+b+c)}.


Any further questions? (**) (**)

Re: What is this used for? Quiz for pilots ....

Posted: Wed Oct 15, 2008 9:34 pm
by DarkHelmet
I am just gonna "where the fox that!"

Might see it in action saturday morning and then I will spill the caboodle... JY obviously adores that frame... Will report back after Saturday!

What is this used for? Quiz for pilots ....

Posted: Thu Oct 16, 2008 4:45 am
by John Young
Hi Guys,

vhpy vhpy vhpy Thanks for the "laffs".

I bought a Mr. Funnel. The only problem is that all fuel filler necks on trikes are at an angle. One can't use the funnel unless you have a Buddie to hold it for you. :shock:

So sEXY Grandpa John made the frame with the front legs set back to accommodate the trike. The frame is very light and easy to handle.

Now I can pour 25 litres of clean filtered fuel into the trike per minute "solo". :idea: It works very well. !!!!

Thanks again for the "laffs" - photo's below.

Regards
John ZU-sEXY