|
RED-DOG
|
 |
« on: June 26, 2018, 01:59:50 PM » |
|
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?
|
|
|
|
|
Logged
|
The older I get, the better I was.
|
|
|
|
celtic
|
|
« Reply #1 on: June 26, 2018, 02:09:28 PM » |
|
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  |
|
|
|
|
Logged
|
Keefy is back But for how long? |
|
|
|
Longines
|
|
« Reply #2 on: June 26, 2018, 02:36:28 PM » |
|
|
|
|
|
|
Logged
|
|
|
|
|
RED-DOG
|
|
« Reply #3 on: June 26, 2018, 03:19:14 PM » |
|
I can't see where to write 5ft plank. |
|
|
|
|
Logged
|
The older I get, the better I was.
|
|
|
|
doubleup
|
|
« Reply #4 on: June 26, 2018, 03:40:09 PM » |
|
it would be in the hypotenuse box but that isn't enough info as you need the bottom line of the triangle as well
|
|
|
|
|
Logged
|
|
|
|
|
RED-DOG
|
|
« Reply #5 on: June 26, 2018, 03:44:22 PM » |
|
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? |
|
|
|
|
Logged
|
The older I get, the better I was.
|
|
|
|
doubleup
|
|
« Reply #6 on: June 26, 2018, 03:53:24 PM » |
|
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? |
|
|
|
|
Logged
|
|
|
|
|
RED-DOG
|
|
« Reply #7 on: June 26, 2018, 04:12:11 PM » |
|
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. |
|
|
|
|
Logged
|
The older I get, the better I was.
|
|
|
|
Longines
|
|
« Reply #8 on: June 26, 2018, 04:16:31 PM » |
|
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.
|
|
|
|
|
Logged
|
|
|
|
|
RED-DOG
|
|
« Reply #9 on: June 26, 2018, 04:22:35 PM » |
|
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. |
|
|
|
|
Logged
|
The older I get, the better I was.
|
|
|
|
doubleup
|
|
« Reply #10 on: June 26, 2018, 04:59:25 PM » |
|
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.
hmmm I put in both the angles and got "computer says no" |
|
|
|
|
Logged
|
|
|
|
|
Longines
|
|
« Reply #11 on: June 26, 2018, 05:41:57 PM » |
|
|
|
|
|
|
Logged
|
|
|
|
|
doubleup
|
|
« Reply #12 on: June 26, 2018, 07:30:47 PM » |
|
for centuries man has got by without reading instructions until something has gone wrong, so I doubt this suddenly changed 17 years ago. |
|
|
|
|
Logged
|
|
|
|
|
Rupert
|
|
« Reply #13 on: June 28, 2018, 07:34:26 AM » |
|
cos theta = adj/hypotenuse
=> hypotenuse * sin theta = height
=> 5ft * sin 25(pi/180) = height
=> height = 2.11308989034ft
|
|
|
|
|
Logged
|
|
|
|
|
RED-DOG
|
|
« Reply #14 on: June 28, 2018, 08:16:15 AM » |
|
cos theta = adj/hypotenuse
=> hypotenuse * sin theta = height
=> 5ft * sin 25(pi/180) = height
=> height = 2.11308989034ft
Amazing. |
|
|
|
|
Logged
|
The older I get, the better I was.
|
|
|
|
Author