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#1 Re: Dark Discussions at Cafe Infinity » Sunami » 2012-05-22 23:45:41



Oh!, I dont know, lets for ease of figures say 20 feet per mile.

Its just clicked now, to calculate this are you going to work backwards from my house then for each mile add on 20 feet etc. until you get to the starting point


#2 Dark Discussions at Cafe Infinity » Sunami » 2012-05-21 20:02:15

Replies: 3

Morning All,

I watched a film the other day called IMPACT or something where something from space hit earth and caused a massive Sunami and I was wondering what if...

I live approx. 65 miles from the nearest coastline and my home town is approx. 128mtr above sea level, lets just say that a big rock hit the sea approx. 100 miles from my house (which would be approx. 40 miles from the coastline) and caused a big wave, forget about the fact that I would probably be dead etc.

Lets also assume that the land increases steadily over the course of 60 miles from sea level to 128mtr above sea level and doesnt go up and down (hills and valleys)

My questions is How tall must this wave be (60 miles away and at sea level) to cover my house by say 50 feet when it gets to my house?

This is probably a stupid question to a stupid problem but thought I'd ask anyway :-)


#3 Re: Help Me ! » Voussoir Formula » 2012-04-25 18:09:49


The picture with the red arrows is exactly what I am trying to achieve.

I need to work out the sizes of each block (angles, lengths etc.) based on 3 criteria, Radius of arch, # of blocks and height of each block.



#4 Re: Help Me ! » Voussoir Formula » 2012-04-24 04:21:17


Sorry, a voussoir is the piece of stone or brick etc. that are wedged shape that make up the arch.

#5 Re: Coder's Corner » I have devised an uncrackable substitution cypher code » 2012-04-24 04:17:43


I wrote a code generator a while back in Delphi.

The following code when deciphered would read ABCDEF


The only drawback with this is that if you wrote a whole sentence, it would be quite a long string, can anyone say how I have done this?

#6 Help Me ! » Voussoir Formula » 2012-04-24 04:08:59

Replies: 5

Evening All,
Does anyone know how to calculate the size of each voussoir for a stone arch
Lets say the following :-

Radius = 24 inch
Voussoir Height = 6 inch
Number of Voussoirs = 9 (this would be 4 either side and 1 in middle as keystone)

This is also based on a Roman Semi Circle arch

I need to know the 4 angles of each vioussoir and the length of the intrados and extrados

I know that this must be a simple formula for you guys but its doing my head lol

Is there any chance of instead of saying x/y+c=gg could you please use the numbers above and show how you get the results

Thanks in advance

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