Beastly Ancient Weapons
The Ballista:
The Ballista, also called the Skorpian, it is designed like a gigantic cross-bow. It was invented by the Ancient Greeks in 800 B.C. The Ballista was designed to shoot large iron clad arrows that could penetrate armor and kill several enemies at a time. The Ballista was highly accurate, and worked by using tension. The Ballista had two arms that were both made of wood, and had ropes attached to each arm they were the springs of the Ballista. The ropes were made of human hair. When the bow-arms of the Ballista were pulled back and the ropes twisted, the bowstring would be pulled back by some sort of winch, and then the Ballista fired.
www.ehow.com/how_2316411_build-model-ballista...
The Ballista's Missles
The Ballista was highly accurate but lacked a long range. The missiles launched by the Ballista were lighter than the missiles of a trebuchet, but could not gain the momentum that the missiles of a trebuchet had. The Ballista can fire up to 1000 missiles a day. The missiles could launch up to 500m!, and packed a lot of fear to the people the missile was being shot at. The missiles were made of sharp wooden poles and darts with iron points.
web.njit.edu/~jds6/
The Physics of The Ballista
The Ballista has a maximum range of 500m! The shots were very accurate. To reach the maximum distance the arrow was shot at a 45 degree angle.
R=V0x*t=500
V0x=cos(45)*V0
R=V0*t*cos(45)
500/(V0*cos(45))=t
And
d=V0*sin(45)*t+.5*a*t2
d=V0*sin(45)*500/(V0*cos(45))+.5*a*(500/(V0*cos(45)))2[/sup]
So the height for half the range, 250m, is
d=V0*sin(45)*t*250m/(V0*cos(45))+.5*a*(250m/(V0*cos(45)))2
And
Vy2=V0y2+2*a*d
Vy=0 at the highest point and
V0y=V0sin(45)
0=(V0sin(45))2+2*a*d
So the height for 250m of range is also
-v2*sin(45)2/(2*a)=d
members.lycos.nl/onager/ballista.html
