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Posted: 5/22/2005 2:13:15 PM EST
[Last Edit: 5/22/2005 2:16:56 PM EST by IchWarrior]
So your standing at the bottom of a water fall, you look up to the top of the falls and for some reason you take not your angle of elevation is 60 degrees.
You go hiking 1000 feet away from the water fall, remaining at the same elevation (Okay, better yet you are on a boat and you float 1000 feet down river. You look up to the top of the falls and your angle of elevation is 57.3 degrees. How tall is the falls? Cant for the life of me figger it out. ETA: My only hunches is that you find a ratio of your angles of elevation and multiply that by the 1000 foot difference... 


This is a simple trig problem. The tangent of your angle of elevation is equal to the unknown height of the falls over the distance you are away from it. That is...
tan(57.3)=x/1000 solve for x. 


I'm lazy anymore...ok, maybe I have always been lazy, but I end up just figuring things like this out in a CAD program.


"It's good to know who hates you, and it's good to be hated by the right people."

i didnt know "simple" and "trig" went in the same sentence. 

"If your lady wants to be treated like a Queen, then she must learn to bow down to the King. The King bows to no one!"

the tangent of an angle = opposite side/adjacent side.
Therefore, tangent(57.3) = x/1000 where x=height of waterfall solve for X 


Actually, you have use trig and algebra.
h = xtan60 = (1000+x)tan57.3 Edited cause I don't know my cos from my tan. Rusty. It's been years, hell decades. 

Fuck 'em. We're the ones with the guns. <IMG SRC=/images/smilies/anim_sniper2.gif border=0 align=middle>
They are not going to stop, ever, until we kick their ass. 
My answer is "perty damn big"



law of sine
a/sinA=b/sinB=c/sinC a= unknown A=57.3 b=1000 B=90 simple enough a/sin57.3=1000/1 a=1000*sin57.3 you can finish it from there 


Problem is b = a + 1000 

Fuck 'em. We're the ones with the guns. <IMG SRC=/images/smilies/anim_sniper2.gif border=0 align=middle>
They are not going to stop, ever, until we kick their ass. 
dont think so. but shit, i did make a mistake.. ok A= 57.3 a=? B=32.7 b=1000 C=90 c=? but other than that, the length of b does not equal the length of a plus its own length... a/sin57.3=1000/sin32.7 a=(1000*sin57.3)/sin32.7 


Yep, because if you were right under the falls the first angle would be 90 degrees. 

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"I swear, put a SWO and a Marine in charge and they will work all night until work is done." 
ok i dont know what formula that is, but i know the law of sine gives hte right answer. 


Aw, hell, you're in trig and can't do that? Don't make me get my calculator out...



I can't even remember the law of sine. It's been too long, so you're WAAAY ahead of me. 

"Ships are prisons for overachievers."
"I swear, put a SWO and a Marine in charge and they will work all night until work is done." 
But: sin R = height of falls/ hypotenuse ::: so I am not sure how that helps. tan R = height of falls / distance 

Fuck 'em. We're the ones with the guns. <IMG SRC=/images/smilies/anim_sniper2.gif border=0 align=middle>
They are not going to stop, ever, until we kick their ass. 
law of sine gets 1557.67 feet high. that tangent formula not only has 2 unknowns, but is set to equal the hypotonuse. why are you guys trying to figure out the hyp? he wants the hight of the falls, not the distance from where the person is, to the hight of the falls. anyway, the hypotonuse is 1851.03 feet tall 


With the hyp and the angle you can always get the opposite leg. 

"Ships are prisons for overachievers."
"I swear, put a SWO and a Marine in charge and they will work all night until work is done." 
so you're using soh cah toa so tangent=oposite over adjacent tan57.3=x/1000 tan57.3*1000=x which is hte hight of the falls x=1557.67 same answer 


You are way off. h is height of the falls or o for opposite side. You don't use both unkowns. Solve for x using the right side of the equation: xtan60 = (1000+x)tan57.3 Where x is the distance from the fall. x +1000 is the second distance. then, h = xtan60 solve for h. The Law of sines BTW concerns any triangle, even oblique, with regards to the ratios btwn angles and opposite sides. IOW the ratio of the sin of one of the angles divided by the oppsite side is the same as all the others. I don't see how it helps. Gee guys, I haven't done this shit since 1983 

Fuck 'em. We're the ones with the guns. <IMG SRC=/images/smilies/anim_sniper2.gif border=0 align=middle>
They are not going to stop, ever, until we kick their ass. 
Ow my head hurts!


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h = xtan60 doesnt make sence. where did you get 60? and x and h are two un knowns 


The first angle, at distance x, is 60 deg. The second angle at distance 1000 + x is 57.3 deg. 

Fuck 'em. We're the ones with the guns. <IMG SRC=/images/smilies/anim_sniper2.gif border=0 align=middle>
They are not going to stop, ever, until we kick their ass. 
SOHCAHTOA... 


tanR = height / distance
tan60 = h / x xtan60 = h tan57.3 = h / (1000 + x) (1000 + x)tan57.3 = h therefore: xtan60 = (1000 + x)tan57.3 tan60/tan57.3 = (1000 + x) / x 1.11x = 1000 + x 0.11x = 1000 x = 1000/0.11= 9091 ft. Therefore: 9091 tan60 = 15746ft high falls. 

Fuck 'em. We're the ones with the guns. <IMG SRC=/images/smilies/anim_sniper2.gif border=0 align=middle>
They are not going to stop, ever, until we kick their ass. 
oh crap, you're right. lets do it this way. C=90 c=who cares A1=60 a1=what we want (w) B1=30 b1=x A2=57.3 a2=w B2=32.7 b2=X+1000 since using hte law of sine on both of these gives... w/sin60=x/sin30 w*sin30/sin60=x w/sin57.3=x/sin32.7 w+1000*sin32.7/sin57.3=x w*sin30/sin60=w+1000*sin32.7/sin57.3 .577w=.477(w+1000) 1.2087w=w+1000 .2087w=1000 w=4790.87feet which doesnt look right 


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Gee, I seem to be fresh out of give a fuck 
looks good to me... 


I get 15,470.7 feet.



That would be more correct. I dropped a few digits during my calcs. 

Fuck 'em. We're the ones with the guns. <IMG SRC=/images/smilies/anim_sniper2.gif border=0 align=middle>
They are not going to stop, ever, until we kick their ass. 
I confirm with this number 

The Machine gun is America's best friend as long as it is owned and fired by U.S. Citizens <img src=/images/smilies/anim_50cal.gif border=0 align=middle>

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