/*
Science & Engineering Encyclopaedia. Copyright Dirac Delta Consultants Ltd. 2001-2002

No part of this document may be reproduced or transmitted in any form or by any mean, electronic or mechanical, including printing, placing on the internet or by any information storage and retrieval system without permission from the Publisher in writing
*/

var xnm=5
var ynm=0
xnme = new Array(xnm)
ynme = new Array(ynm)
xtxt = new Array(xnm)
ytxt = new Array(ynm)
xunt = new Array(xnm)
yunt = new Array(ynm)
xvrb = new Array(xnm)
yvrb = new Array(ynm)


frm="motion"
scrp="equmot"
ttle="Equations of Motion"
xnme[1]="u"
xtxt[1]="start velocity, u"
xunt[1]="ms<sup>-1</sup>"
xnme[2]="v"
xtxt[2]="end velocity, v"
xunt[2]="ms<sup>-1</sup>"
xnme[3]="a"
xtxt[3]="acceleration, a"
xunt[3]="ms<sup>-2</sup>"
xnme[4]="t"
xtxt[4]="time, t"
xunt[4]="s"
xnme[5]="s"
xtxt[5]="distance travelled, s"
xunt[5]="m"


function equmot(){
utxt=document.motion.u.value
vtxt=document.motion.v.value
atxt=document.motion.a.value
ttxt=document.motion.t.value
stxt=document.motion.s.value
xvrb[1]=parseFloat(utxt)
xvrb[2]=parseFloat(vtxt)
xvrb[3]=parseFloat(atxt)
xvrb[4]=parseFloat(ttxt)
xvrb[5]=parseFloat(stxt)



if (utxt.length==0) {
	if (vtxt.length==0) {
		xvrb[1]=(xvrb[5]-0.5*xvrb[3]*xvrb[4]*xvrb[4])/xvrb[4]
		xvrb[2]=xvrb[1]+xvrb[3]*xvrb[4]
		document.motion.v.value=xvrb[2]
	}

	if (atxt.length==0) {
		xvrb[1]=2*xvrb[5]/xvrb[4]-xvrb[2]
		xvrb[3]=(xvrb[2]-xvrb[1])/xvrb[4]
		document.motion.a.value=xvrb[3]
	}

	if (ttxt.length==0) {
		xvrb[1]=Math.sqrt(xvrb[2]*xvrb[2]-2*xvrb[3]*xvrb[5])
		xvrb[4]=(xvrb[2]-xvrb[1])/xvrb[3]
		document.motion.t.value=xvrb[4]
	}

	if (stxt.length==0) {
		xvrb[1]=xvrb[2]-xvrb[3]*xvrb[4]
		xvrb[5]=0.5*(xvrb[1]+xvrb[2])*xvrb[4]
		document.motion.s.value=xvrb[5]
	}

document.motion.u.value=xvrb[1]
}

if (vtxt.length==0) {

	if (atxt.length==0) {
		xvrb[2]=2*xvrb[5]/xvrb[4]-xvrb[1]
		xvrb[3]=(xvrb[2]-xvrb[1])/xvrb[4]
		document.motion.a.value=xvrb[3]
	}

	if (ttxt.length==0) {
		xvrb[2]=Math.sqrt(xvrb[1]*xvrb[1]+2*xvrb[3]*xvrb[5])
		xvrb[4]=(xvrb[2]-xvrb[1])/xvrb[3]
		document.motion.t.value=xvrb[4]
	}

	if (stxt.length==0) {
		xvrb[2]=xvrb[1]+xvrb[3]*xvrb[4]
		xvrb[5]=0.5*(xvrb[1]+xvrb[2])*xvrb[4]
		document.motion.s.value=xvrb[5]
	}


document.motion.v.value=xvrb[2]
}

if (atxt.length==0) {

	if (ttxt.length==0) {
		xvrb[4]=2*xvrb[5]/(xvrb[1]+xvrb[2])
		xvrb[3]=(xvrb[2]-xvrb[1])/xvrb[4]
		document.motion.t.value=xvrb[4]
	}

	if (stxt.length==0) {
		xvrb[3]=(xvrb[2]-xvrb[1])/xvrb[4]
		xvrb[5]=0.5*(xvrb[1]+xvrb[2])*xvrb[4]
		document.motion.s.value=xvrb[5]
	}


document.motion.a.value=xvrb[3]
}

if (ttxt.length==0) {

	if (stxt.length==0) {
		xvrb[4]=(xvrb[2]-xvrb[1])/xvrb[3]
		xvrb[5]=0.5*(xvrb[1]+xvrb[2])*xvrb[4]
		document.motion.s.value=xvrb[5]
	}

document.motion.t.value=xvrb[4]
}

}