#!/usr/bin/gnuplot

# astroblaster.plt
# Vypocet cinnosti "Astroblasteru" - 4 nasobneho razu.
# Miroslav Broz (miroslav.broz@email.cz), Jan 11th 2008

mm=1.e-3
d1=45*mm	# m; prumery balonku
d2=35*mm
d3=25*mm
d4=20*mm

rho = 1300.	# kg/m^3; hustota gumy

m(d) = 4./3.*pi*(d/2.)**3.*rho	# hmotnost
m1=m(d1)
m2=m(d2)
m3=m(d3)
m4=m(d4)

gram = 1.e-3
print "\nhmotnosti balonku:"
print "m1= ", m1/gram, " g"
print "m2= ", m2/gram, " g"
print "m3= ", m3/gram, " g"
print "m4= ", m4/gram, " g"

m0=6.e24;	# kg; hmotnost Zeme
v0=0.

########################################################################

h=1	# m
print "\npocatecni vyska:"
print "h = ", h, " m"

g = 9.81	# m/s^2; tihove zrychleni
v1=-sqrt(2.*g*h)
v2=v1
v3=v1
v4=v1

print "\nrychlosti pred razy:"
print "v0 = ", v0, " m/s (Zeme je v klidu)"
print "v1 = ", v1, " m/s"
print "v2 = ", v2, " m/s"
print "v3 = ", v3, " m/s"
print "v4 = ", v4, " m/s"

########################################################################

raz1(m1,m2,v1,v2) = ((m1-m2)*v1 + 2*m2*v2) / (m1+m2)	# rychlosti po razu
raz2(m1,m2,v1,v2) = ((m2-m1)*v2 + 2*m1*v1) / (m1+m2)

print "\n1. raz (Zeme-1. balonek):"
w0=raz1(m0,m1,v0,v1)
w1=raz2(m0,m1,v0,v1)
print "w0 = ", w0, " m/s"
print "w1 = ", w1, " m/s = ", w1/v1, " v1"

print "\n2. raz (1. a 2. balonek):"
v1=w1
w1=raz1(m1,m2,v1,v2)
w2=raz2(m1,m2,v1,v2)
print "w1 = ", w1, " m/s = ", w1/v1, " v1"
print "w2 = ", w2, " m/s = ", w2/v1, " v1"

print "\n3. raz (2. a 3. balonek):"
v2=w2
w2=raz1(m2,m3,v2,v3)
w3=raz2(m2,m3,v2,v3)
print "w2 = ", w2, " m/s = ", w2/v1, " v1"
print "w3 = ", w3, " m/s = ", w3/v1, " v1"

print "\n4. raz (3. a 4. balonek):"
v3=w3
w3=raz1(m3,m4,v3,v4)
w4=raz2(m3,m4,v3,v4)
print "w3 = ", w3, " m/s = ", w3/v1, " v1"
print "w4 = ", w4, " m/s = ", w4/v1, " v1"

########################################################################

print "\nhybnosti balonku po razech:"
p1 = m1*w1 
p2 = m2*w2
p3 = m3*w3
print "p1 = ", p1, " kg m/s"
print "p2+p3 = ", p2+p3, "kg m/s"

print "\nkonecna vyska:"
h_ = w4**2./(2.*g)
print "h' = ", h_, " m = ", h_/h, " h"

print "\nTo je hrozne moc!!! :-)"