blonde poker forum

If you lay a 5ft plank on on the floor, (No Celtic jokes please) and then raise one end 25 degrees, how hight from the floor will the raised end be?

loool :)

0.00320201383517491 furlongs.

yw.

http://www.g3asr.co.uk/calculators/triangle.htm

I can't see where to write 5ft plank.

it would be in the hypotenuse box but that isn't enough info as you need the bottom line of the triangle as well

Surely there is enough information in the original question though?

don't you just have the length of one side and the angles? 

I'm going to make some roof trusses to support metal tiles. The recommended angle for metal tile installation is 25 degrees, so what I need to know is how high the apex needs to be (above gutter hight) to give me the correct angle assuming that each side of the roof, (or two sides of the triangle) are 5ft long.

If you put 25 degrees in bottom angle and 60 (inches) in hypotenuse, you get 25.36" as the height and 54.38" as the base length.

Yep, I can live with that.

 Thanks.

hmmm I put in both the angles and got "computer says no"

enter EITHER 2 sides OR 1 side & 1 angle

We didn't need your fancy error handling stuff 17 years ago, we had users that read the instructions  ;whistle;  ;snoopy'sguns;  :)up

for centuries man has got by without reading instructions until something has gone wrong, so I doubt this suddenly changed 17 years ago.  :)

cos theta = adj/hypotenuse

=> hypotenuse * sin theta = height
=> 5ft * sin 25(pi/180) = height
=> height = 2.11308989034ft

Amazing.

Incredible. I wish i could understand how you get to that.

http://www.bbc.co.uk/schools/gcsebitesize/maths/geometry/trigonometryrev1.shtml

GCSE maths

if you put calculator in degrees you don't need to convert to radians. Also top line was wrong formula, lol

I make it about the same.

...and we're back to 5ft planks.

Too easy Tom , too easy.

I know, I feel dirty now.

The closest I could get to working out 25 degrees of elevation was 4in up for every 12in of length.

So 5tft is 5x4in =25in.

If course, as I raise the plank it becomes shorter horizontally so it's just a rough estimate rather than an actual answerer.

I think I'll just lift it up until it looks right.

Can we, or I suppose the question is should we decimalise an imperial measurement?

2.113ft is pretty meaningless isn't it? Some people could easily mistake this for 2' 11" when it's actually about 2' 1 1/3"

Probably best to convert 5ft in to metric first which won't go down well but it'll give a far more accurate way of getting that vertical height.

That was always going to be Tom's solution.....