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Lecture 2 Thur. 8.27.2015
Analysis of 1D 2-Body Collisions(Ch. 3 to Ch. 5 of Unit 1)
Review of elastic Kinetic Energy ellipse geometryThe X2 Superball pen launcher *
Perfectly elastic “ka-bong” velocity amplification effects (Faux-Flubber)
Geometry of X2 launcher bouncing in boxIndependent Bounce Model (IBM)Geometric optimization and range-of-motion calculation(s)Integration of (V1,V2) data to space-time plots (y1(t),t) and (y2(t),t) plotsIntegration of (V1,V2) data to space-space plots (y1, y2)
Multiple collisions calculated by matrix operator products Matrix or tensor algebra of 1-D 2-body collisions
Ellipse rescaling-geometry and reflection-symmetry analysisRescaling KE ellipse to circle
How this relates to Lagrangian, l’Etrangian, and Hamiltonian mechanics in Ch. 12
*Launch Superball Collision Simulator http://www.uark.edu/ua/modphys/markup/BounceItWeb.html
1Friday, August 28, 2015
VVW
100
110
120
-120
(60,10)
Initial-point
Final“Ka-Bong”-point
a=√=60.21
2·KE
MSUV
b=√=120.42
2·KEmVW
Elastic
Kinetic
Energy
ellipse
(KE=7,250)
Momentum
PTotal=250
line
(50,50)
(40,90)
MSUV=4M
SUV=4
mVW=1m
VW=1
VSUV
Fig. 3.1 ain Unit 1
a=√=55.9
2·IE
MSUV
b=√=111.8
2·IEmVW
COM
Energy
ellipse
(ECOM=1,000)
elastic
FIN
IN
inlastic
FIN is
VCOM
point
Inelastic
Kinetic
Energy
ellipse
(IE=6,250)
Fig. 3.1 bin Unit 1
Review of elastic Kinetic Energy ellipse geometry
2Friday, August 28, 2015
M1=70gmM1=70gm
M0=10kgM0=10kgbounceplatebounceplate
RRrrd
Superballpenetrationdepthr22Rd=
SuperballSuperball
ballpointpen
M2=10gm
ballpointpen
M2=10gm
The X-2pen-
launcher
The X-2pen-
launcher
The X-2 Pen launcher and Superball Collision Simulator*
*Launch Superball Collision Simulator http://www.uark.edu/ua/modphys/markup/BounceItWeb.html
3Friday, August 28, 2015
M1=70gmM1=70gm
M0=10kgM0=10kgbounceplatebounceplate
RRrrd
Superballpenetrationdepthr22Rd=
SuperballSuperball
ballpointpen
M2=10gm
ballpointpen
M2=10gm
The X-2pen-
launcher
The X-2pen-
launcherFig. 4.1 and Fig. 4.3
in Unit 1
M1
m2BANG!M1
(BiggerBANG!)
(StillBiggerBANG!)
m2
M1M1
m2
Bang1!
Bang2!M1
m2
(a) Super-elastic 2nd-body bounce (b) 2-Bang Model (c) n-BodySupernovaSuperballs
m2
-1.0
1.0
1.0
0.5
2.0
m2 Velocity axisVym2
m1 Velocity axisVym1
(0,0)
Bang-1(01)INIT point at(-1.0,-1.0)
(a)Bang-1(01)
Fig. 4.4a-bin Unit 1
Bang-1(01)FINAL point(+1.0,-1.0)
This 1st bang is a floor-bounce ofM1 off very massive plate/Earth M0
2.02.01st bang:mass (M0)vs. mass (M1)
2nd or 3rd bangs:mass (M1) vs. mass (M2)
1st bang:M1 off floor
*Launch Superball Collision Simulator http://www.uark.edu/ua/modphys/markup/BounceItWeb.html
4Friday, August 28, 2015
M1=70gmM1=70gm
M0=10kgM0=10kgbounceplatebounceplate
RRrrd
Superballpenetrationdepthr22Rd=
SuperballSuperball
ballpointpen
M2=10gm
ballpointpen
M2=10gm
The X-2pen-
launcher
The X-2pen-
launcherFig. 4.1 and Fig. 4.3
in Unit 1
M1
m2BANG!M1
(BiggerBANG!)
(StillBiggerBANG!)
m2
M1M1
m2
Bang1!
Bang2!M1
m2
(a) Super-elastic 2nd-body bounce (b) 2-Bang Model (c) n-BodySupernovaSuperballs
m2
-1.0
1.0
1.0
0.5
2.0
m2 Velocity axisVym2
m1 Velocity axisVym1
(0,0)
Bang-1(01)INIT point at(-1.0,-1.0)
(a)Bang-1(01)
Fig. 4.4a-bin Unit 1
Bang-1(01)FINAL point(+1.0,-1.0)
This 1st bang is a floor-bounce ofM1 off very massive plate/Earth M0
2.02.01st bang:mass (M0)vs. mass (M1)
2nd or 3rd bangs:mass (M1) vs. mass (M2)
M1 mirror reflection
thru m2 axis
1st bang:M1 off floor
5Friday, August 28, 2015
M1=70gmM1=70gm
M0=10kgM0=10kgbounceplatebounceplate
RRrrd
Superballpenetrationdepthr22Rd=
SuperballSuperball
ballpointpen
M2=10gm
ballpointpen
M2=10gm
The X-2pen-
launcher
The X-2pen-
launcherFig. 4.1 and Fig. 4.3
in Unit 1
M1
m2BANG!M1
(BiggerBANG!)
(StillBiggerBANG!)
m2
M1M1
m2
Bang1!
Bang2!M1
m2
(a) Super-elastic 2nd-body bounce (b) 2-Bang Model (c) n-BodySupernovaSuperballs
m2
-1.0
1.0
1.0
0.5
2.0
m2 Velocity axisVym2
m1 Velocity axisVym1
(0,0)
Bang-1(01)INIT point at(-1.0,-1.0)
(a)Bang-1(01)
Fig. 4.4a-bin Unit 1
Bang-1(01)FINAL point(+1.0,-1.0)
This 1st bang is a floor-bounce ofM1 off very massive plate/Earth M0
2.02.01st bang:mass (M0)vs. mass (M1)
2nd or 3rd bangs:mass (M1) vs. mass (M2)
M1 mirror reflection
thru m2 axis
1st bang:M1 off floor
2nd bang:m2 off M1
*Launch Superball Collision Simulator http://www.uark.edu/ua/modphys/markup/BounceItWeb.html
6Friday, August 28, 2015
M1=70gmM1=70gm
M0=10kgM0=10kgbounceplatebounceplate
RRrrd
Superballpenetrationdepthr22Rd=
SuperballSuperball
ballpointpen
M2=10gm
ballpointpen
M2=10gm
The X-2pen-
launcher
The X-2pen-
launcherFig. 4.1 and Fig. 4.3
in Unit 1
M1
m2BANG!M1
(BiggerBANG!)
(StillBiggerBANG!)
m2
M1M1
m2
Bang1!
Bang2!M1
m2
(a) Super-elastic 2nd-body bounce (b) 2-Bang Model (c) n-BodySupernovaSuperballs
m2
-1.0
1.0
1.0
0.5
2.0
m2 Velocity axisVym2
m1 Velocity axisVym1
(0,0)
Bang-1(01)INIT point at(-1.0,-1.0)
(a)Bang-1(01)
Fig. 4.4a-bin Unit 1
Bang-1(01)FINAL point(+1.0,-1.0)
This 1st bang is a floor-bounce ofM1 off very massive plate/Earth M0
2.02.01st bang:mass (M0)vs. mass (M1)
2nd or 3rd bangs:mass (M1) vs. mass (M2)
M1 mirror reflection
thru m2 axis
1st bang:M1 off floor
2nd bang:m2 off M1
3rd bang:m2 off ceiling
7Friday, August 28, 2015
M1=70gmM1=70gm
M0=10kgM0=10kg
bounce
plate
bounce
plate
RRrr
d
Superball
penetration
depth
r2
2Rd=
SuperballSuperball
ballpoint
pen
M2=10gm
ballpoint
pen
M2=10gm
The X-2pen-
launcher
The X-2pen-
launcherFig. 4.1 and Fig. 4.3
in Unit 1
M1
m2BANG!M1
(BiggerBANG!)
(StillBiggerBANG!)
m2
M1M1
m2
Bang1!
Bang2!M1
m2
(a) Super-elastic 2nd-body bounce (b) 2-Bang Model (c) n-BodySupernovaSuperballs
m2
-1.0
1.0
1.0
0.5
2.0
m2 Velocity axis
Vym2
m1 Velocity axis
Vym1
(0,0)
Bang-1(01)
INIT point at
(-1.0,-1.0)
(a)Bang-1(01)
Fig. 4.4a-bin Unit 1
INITIAL
FINAL (Elastic)
0 V1
(b)
M1<<M
0
V0
FINAL
(Totally Inelastic)COM
FI
top of a very long ellipse
Fig. 4.2bin Unit 1(slightly modified)
Bang-1(01)
FINAL point
(+1.0,-1.0)
This 1st bang is a floor-bounce of
M1off very massive plate/Earth M
0
2.02.01st bang:
mass (M0)vs. mass (M
1)
2nd or 3rd bangs:
mass (M1) vs. mass (M
2)
V1
V0Very skinny Energy ellipse for M0>>M1
M1 mirror reflection
thru m2 axis
1st bang:M1 off floor
2nd bang:m2 off M1
3rd bang:m2 off ceiling
1st bang M1 off floor “skinny-ellipse” 8Friday, August 28, 2015
M1=70gmM1=70gm
M0=10kgM0=10kg
bounce
plate
bounce
plate
RRrr
d
Superball
penetration
depth
r2
2Rd=
SuperballSuperball
ballpoint
pen
M2=10gm
ballpoint
pen
M2=10gm
The X-2pen-
launcher
The X-2pen-
launcherFig. 4.1 and Fig. 4.3
in Unit 1
M1
m2BANG!M1
(BiggerBANG!)
(StillBiggerBANG!)
m2
M1M1
m2
Bang1!
Bang2!M1
m2
(a) Super-elastic 2nd-body bounce (b) 2-Bang Model (c) n-BodySupernovaSuperballs
m2
-1.0
1.0
1.0
0.5
2.0
m2 Velocity axis
Vym2
m1 Velocity axis
Vym1
(0,0)
Bang-1(01)
INIT point at
(-1.0,-1.0)
(a)Bang-1(01)
Fig. 4.4a-bin Unit 1
INITIAL
FINAL (Elastic)
0 V1
(b)
M1<<M
0
V0
FINAL
(Totally Inelastic)COM
FI
top of a very long ellipse
INITIAL
FINAL (Elastic)
0 V1
COM
(a)
M1>>M
2
V2
FINAL
(Totally Inelastic)
F0
I0
(+) side of a
very tall
ellipse
(-) side of a
very tall
ellipse
Fig. 4.2bin Unit 1(slightly modified)
Bang-1(01)
FINAL point
(+1.0,-1.0)
This 1st bang is a floor-bounce of
M1off very massive plate/Earth M
0
Fig. 4.2ain Unit 1(slightly modified)
Later is a ceiling-bounce of
M2off ceiling/Earth M
1
2.02.01st bang:
mass (M0)vs. mass (M
1)
2nd or 3rd bangs:
mass (M1) vs. mass (M
2)
Later:
V1
V0Very skinny Energy ellipse for M0>>M1
M1 mirror reflection
thru m2 axis
1st bang:M1 off floor
2nd bang:m2 off M1
3rd bang:m2 off ceiling
1st bang M1 off floor “skinny-ellipse” 9Friday, August 28, 2015
M1=70gmM1=70gm
M0=10kgM0=10kg
bounce
plate
bounce
plate
RRrr
d
Superball
penetration
depth
r2
2Rd=
SuperballSuperball
ballpoint
pen
M2=10gm
ballpoint
pen
M2=10gm
The X-2pen-
launcher
The X-2pen-
launcherFig. 4.1 and Fig. 4.3
in Unit 1
M1
m2BANG!M1
(BiggerBANG!)
(StillBiggerBANG!)
m2
M1M1
m2
Bang1!
Bang2!M1
m2
(a) Super-elastic 2nd-body bounce (b) 2-Bang Model (c) n-BodySupernovaSuperballs
m2
-1.0
1.0
1.0
0.5
2.0
m2 Velocity axis
Vym2
m1 Velocity axis
Vym1
(0,0)
Bang-1(01)
INIT point at
(-1.0,-1.0)
(a)Bang-1(01)
Fig. 4.4a-bin Unit 1
INITIAL
FINAL (Elastic)
0 V1
(b)
M1<<M
0
V0
FINAL
(Totally Inelastic)COM
FI
top of a very long ellipse
INITIAL
FINAL (Elastic)
0 V1
COM
(a)
M1>>M
2
V2
FINAL
(Totally Inelastic)
F0
I0
(+) side of a
very tall
ellipse
(-) side of a
very tall
ellipse
Fig. 4.2bin Unit 1(slightly modified)
Bang-1(01)
FINAL point
(+1.0,-1.0)
This 1st bang is a floor-bounce of
M1off very massive plate/Earth M
0
Fig. 4.2ain Unit 1(slightly modified)
Later is a ceiling-bounce of
M2off ceiling/Earth M
1
2.02.01st bang:
mass (M0)vs. mass (M
1)
2nd or 3rd bangs:
mass (M1) vs. mass (M
2)
Later:
V1
V0Very skinny Energy ellipse for M0>>M1
V0
V2
M1 mirror reflection
thru m2 axis
1st bang:M1 off floor
2nd bang:m2 off M1
3rd bang:m2 off ceiling
1st bang M1 off floor “skinny-ellipse” 10Friday, August 28, 2015
Geometry of X2 launcher bouncing in boxIndependent Bounce Model (IBM)Geometric optimization and range-of-motion calculation(t)Integration of (V1,V2) data to space-time plots (y1(t),t) and (y2(t),t) plotsIntegration of (V1,V2) data to space-space plots (y1, y2)
11Friday, August 28, 2015
M1=70gmM1=70gm
M0=10kgM0=10kg
bounce
plate
bounce
plate
RRrr
d
Superball
penetration
depth
r2
2Rd=
SuperballSuperball
ballpoint
pen
M2=10gm
ballpoint
pen
M2=10gm
The X-2pen-
launcher
The X-2pen-
launcherFig. 4.1 and Fig. 4.3
in Unit 1
M1
m2BANG!M1
(BiggerBANG!)
(StillBiggerBANG!)
m2
M1M1
m2
Bang1!
Bang2!M1
m2
(a) Super-elastic 2nd-body bounce (b) 2-Bang Model (c) n-BodySupernovaSuperballs
m2
-1.0
1.0
1.0
0.5
2.0
m2 Velocity axis
Vym2
m1 Velocity axis
Vym1
(0,0)
Bang-1(01)
INIT point at
(-1.0,-1.0)
(a)Bang-1(01)
Fig. 4.4a-bin Unit 1
Bang-1(01)
FINAL point
(+1.0,-1.0)
This 1st bang is a floor-bounce of
M1off very massive plate/Earth M
0
2.02.01st bang:
mass (M0)vs. mass (M
1)
-7
+1
1.0
1.0
0.5
2.0
m1 Velocity axis
Vym1
(0,0)
COM-point at
(0.75,0.75))
-1.0
Bang-2(12)
INIT point at
(+1.0,-1.0)
Bang-2(12)
FINAL point
(0.5,2.5)
(b)Bang-2(12)
2nd bang:
(M1)vs.(M
2)
M1 mirror reflection
thru m2 axis
12Friday, August 28, 2015
Geometry of X2 launcher bouncing in boxIndependent Bounce Model (IBM)Geometric optimization and range-of-motion calculation(s)Integration of (V1,V2) data to space-time plots (y1(t),t) and (y2(t),t) plotsIntegration of (V1,V2) data to space-space plots (y1, y2)
13Friday, August 28, 2015
M1=70gmM1=70gm
M0=10kgM0=10kgbounceplatebounceplate
RRrrd
Superballpenetrationdepthr22Rd=
SuperballSuperball
ballpointpen
M2=10gm
ballpointpen
M2=10gm
The X-2pen-
launcher
The X-2pen-
launcherFig. 4.1 and Fig. 4.3
in Unit 1
M1
m2BANG!M1
(BiggerBANG!)
(StillBiggerBANG!)
m2
M1M1
m2
Bang1!
Bang2!M1
m2
(a) Super-elastic 2nd-body bounce (b) 2-Bang Model (c) n-BodySupernovaSuperballs
m2
Fig. 4.5ain Unit 1Start at
(1.0,-1.0)
1.0
1.0
-1.0
0.5
2.0 C
L
P
L is 15::1
P is 7::1C is 4::1
Line CPLis elastic collisionfinal pt. locus fordifferentmomentumslopesormassratiosM1::M2
M2 Velocity axisV2
M1 Velocity axis V1(0,0)
3.0
Bang-2(12)FINALpoints
(a)
14Friday, August 28, 2015
M1=70gmM1=70gm
M0=10kgM0=10kgbounceplatebounceplate
RRrrd
Superballpenetrationdepthr22Rd=
SuperballSuperball
ballpointpen
M2=10gm
ballpointpen
M2=10gm
The X-2pen-
launcher
The X-2pen-
launcherFig. 4.1 and Fig. 4.3
in Unit 1
M1
m2BANG!M1
(BiggerBANG!)
(StillBiggerBANG!)
m2
M1M1
m2
Bang1!
Bang2!M1
m2
(a) Super-elastic 2nd-body bounce (b) 2-Bang Model (c) n-BodySupernovaSuperballs
m2
Fig. 4.5a-bin Unit 1Start at
(1.0,-1.0)
1.0
1.0
-1.0
0.5
2.0 C
L
P
L is 15::1
P is 7::1C is 4::1
Line CPLis elastic collisionfinal pt. locus fordifferentmomentumslopesormassratiosM1::M2
1.0
1.0
-1.0
0.5
2.0 C
L
P
L is 15::1
P is 7::1C is 4::1
II iiss 11::::00oorr ∞∞::::11II
MM iiss 33::::11
MM
3.0M2 Velocity axisV2
M2 Velocity axisV2
M1 Velocity axis V1 M1 Velocity axis V1(0,0) (0,0)
3.0
D is 2::1
Uis 1::1
Bang-2(12)FINALpoints
(a) (b)
-1.0
U2
U1
15Friday, August 28, 2015
Geometry of X2 launcher bouncing in boxIndependent Bounce Model (IBM)Geometric optimization and range-of-motion calculation(s)Integration of (V1,V2) data to space-time plots (y1(t),t) and (y2(t),t) plotsIntegration of (V1,V2) data to space-space plots (y1, y2)
16Friday, August 28, 2015
Ceiling at y=7.1
Time
t-axis
Height
y-axisVy1
Vy2
1.0
1.0
-1.0
0.5
Velocity Vy2vs. V
y1Plot
Position y vs. Time t Plot
Vy1=+1.0
Vy2=-0.5
means M1is
somewhere
on some path of slope +1.0
slope
1/1=+11
1
slope
-0.5/1=-0.5-0.5
1means M
2is
somewhere
on some path of slope -0.5
Floor at y=0
-0.5
1
y
-0.5
+1.0
Geometric “Integration” (Converting Velocity data to Spacetime)
17Friday, August 28, 2015
Ceiling at y=7.1
Time
t-axis
Height
y-axisVy1
Vy2
1.0
1.0
-1.0
0.5
Velocity Vy2vs. V
y1Plot
Position y vs. Time t Plot
Vy1=+1.0
Vy2=-0.5
means M1is
somewhere
on some path of slope +1.0
slope
1/1=+11
1
slope
-0.5/1=-0.5-0.5
1means M
2is
somewhere
on some path of slope -0.5
Floor at y=0
-0.5
1
y
-0.5
+1.0
Geometric “Integration” (Converting Velocity data to Spacetime)
18Friday, August 28, 2015
Ceiling at y=7.1
Time
t-axis
Height
y-axisVy1
Vy2
1.0
1.0
-1.0
0.5
Velocity Vy2vs. V
y1Plot
Position y vs. Time t Plot
Vy1=+1.0
Vy2=-0.5
means M1is
somewhere
on some path of slope +1.0
slope
1/1=+11
1
slope
-0.5/1=-0.5-0.5
1means M
2is
somewhere
on some path of slope -0.5
Floor at y=0
-0.5
1
y
-0.5
+1.0
Geometric “Integration” (Converting Velocity data to Spacetime)
Until you specifyinitial conditions y0(t0)…
...you don’t know whatvy-line to use
19Friday, August 28, 2015
Ceiling at y=7.1
Time
t-axis
Height
y-axisVy1
Vy2
1.0
1.0
-1.0
0.5
Velocity Vy2vs. V
y1Plot
Position y vs. Time t Plot
Vy1=+1.0
Vy2=-0.5
means M1is
somewhere
on some path of slope +1.0
slope
1/1=+11
1
slope
-0.5/1=-0.5-0.5
1means M
2is
somewhere
on some path of slope -0.5
Floor at y=0
-0.5
1
y
-0.5
+1.0
Bang-2(12)
position
Ceiling at y=7
Time
t-axis
Height
y-axis
slope
-1
slope
+1
Bang-1(01)
position
y2(0)=3
Vy1
Vy2
1.0
-1.0
0.5
(Vy1,Vy2)=(+1.0,-1.0)
y
(a) Vy2vs. V
y1Plot of Bang-1
(01) (b) y vs. t Plot of Bang-1(01)
Bang-1(01) Bounces (-1,-1) to (+1,-1)
(Vy1,Vy2)=(-1.0,-1.0)
(y=1,t=2)(y=0,t=1)
y1(0)=1
0.5
-1.0 -0.5
-0.5
??
??Floor at y=0
Geometric “Integration” (Converting Velocity data to Spacetime)
Fig. 4.6a-bin Unit 1
Until you specifyinitial conditions y0(t0)…
...you don’t know whichvy-lines to use
initial conditions y1(0)
...and y2(0)
20Friday, August 28, 2015
Ceiling at y=7.1
Time
t-axis
Height
y-axisVy1
Vy2
1.0
1.0
-1.0
0.5
Velocity Vy2vs. V
y1Plot
Position y vs. Time t Plot
Vy1=+1.0
Vy2=-0.5
means M1is
somewhere
on some path of slope +1.0
slope
1/1=+11
1
slope
-0.5/1=-0.5-0.5
1means M
2is
somewhere
on some path of slope -0.5
Floor at y=0
-0.5
1
y
-0.5
+1.0
Bang-2(12)
position
Ceiling at y=7
Time
t-axis
Height
y-axis
slope
-1
slope
+1
Bang-1(01)
position
y2(0)=3
Vy1
Vy2
1.0
-1.0
0.5
(Vy1,Vy2)=(+1.0,-1.0)
y
(a) Vy2vs. V
y1Plot of Bang-1
(01) (b) y vs. t Plot of Bang-1(01)
Bang-1(01) Bounces (-1,-1) to (+1,-1)
(Vy1,Vy2)=(-1.0,-1.0)
(y=1,t=2)(y=0,t=1)
y1(0)=1
0.5
-1.0 -0.5
-0.5
??
??Floor at y=0
Geometric “Integration” (Converting Velocity data to Spacetime)
Fig. 4.6a-bin Unit 1
Until you specifyinitial conditions y0(t0)…
...you don’t know whichvy-lines to use
initial conditions y1(0)
...and y2(0)
21Friday, August 28, 2015
Ceiling at y=7.1
Time
t-axis
Height
y-axisVy1
Vy2
1.0
1.0
-1.0
0.5
Velocity Vy2vs. V
y1Plot
Position y vs. Time t Plot
Vy1=+1.0
Vy2=-0.5
means M1is
somewhere
on some path of slope +1.0
slope
1/1=+11
1
slope
-0.5/1=-0.5-0.5
1means M
2is
somewhere
on some path of slope -0.5
Floor at y=0
-0.5
1
y
-0.5
+1.0
Bang-2(12)
position
Ceiling at y=7
Time
t-axis
Height
y-axis
slope
-1
slope
+1
Bang-1(01)
position
y2(0)=3
Vy1
Vy2
1.0
-1.0
0.5
(Vy1,Vy2)=(+1.0,-1.0)
y
(a) Vy2vs. V
y1Plot of Bang-1
(01) (b) y vs. t Plot of Bang-1(01)
Bang-1(01) Bounces (-1,-1) to (+1,-1)
(Vy1,Vy2)=(-1.0,-1.0)
(y=1,t=2)(y=0,t=1)
y1(0)=1
0.5
-1.0 -0.5
-0.5
??
??Floor at y=0
Geometric “Integration” (Converting Velocity data to Spacetime)
Fig. 4.6a-bin Unit 1
Until you specifyinitial conditions y0(t0)…
...you don’t know whichvy-lines to use
initial conditions y1(0)
...and y2(0)
22Friday, August 28, 2015
Ceiling at y=7.1
Time
t-axis
Height
y-axisVy1
Vy2
1.0
1.0
-1.0
0.5
Velocity Vy2vs. V
y1Plot
Position y vs. Time t Plot
Vy1=+1.0
Vy2=-0.5
means M1is
somewhere
on some path of slope +1.0
slope
1/1=+11
1
slope
-0.5/1=-0.5-0.5
1means M
2is
somewhere
on some path of slope -0.5
Floor at y=0
-0.5
1
y
-0.5
+1.0
Bang-2(12)
position
Ceiling at y=7
Time
t-axis
Height
y-axis
slope
-1
slope
+1
Bang-1(01)
position
y2(0)=3
Vy1
Vy2
1.0
-1.0
0.5
(Vy1,Vy2)=(+1.0,-1.0)
y
(a) Vy2vs. V
y1Plot of Bang-1
(01) (b) y vs. t Plot of Bang-1(01)
Bang-1(01) Bounces (-1,-1) to (+1,-1)
(Vy1,Vy2)=(-1.0,-1.0)
(y=1,t=2)(y=0,t=1)
y1(0)=1
0.5
-1.0 -0.5
-0.5
??
??Floor at y=0
Geometric “Integration” (Converting Velocity data to Spacetime)
Fig. 4.6a-bin Unit 1
Until you specifyinitial conditions y0(t0)…
...you don’t know whichvy-lines to use
initial conditions y1(0)
...and y2(0)
23Friday, August 28, 2015
Ceiling at y=7.1
Time
t-axis
Height
y-axisVy1
Vy2
1.0
1.0
-1.0
0.5
Velocity Vy2vs. V
y1Plot
Position y vs. Time t Plot
Vy1=+1.0
Vy2=-0.5
means M1is
somewhere
on some path of slope +1.0
slope
1/1=+11
1
slope
-0.5/1=-0.5-0.5
1means M
2is
somewhere
on some path of slope -0.5
Floor at y=0
-0.5
1
y
-0.5
+1.0
Bang-2(12)
position
Ceiling at y=7
Time
t-axis
Height
y-axis
slope
-1
slope
+1
Bang-1(01)
position
y2(0)=3
Vy1
Vy2
1.0
-1.0
0.5
(Vy1,Vy2)=(+1.0,-1.0)
y
(a) Vy2vs. V
y1Plot of Bang-1
(01) (b) y vs. t Plot of Bang-1(01)
Bang-1(01) Bounces (-1,-1) to (+1,-1)
(Vy1,Vy2)=(-1.0,-1.0)
(y=1,t=2)(y=0,t=1)
y1(0)=1
0.5
-1.0 -0.5
-0.5
??
??Floor at y=0
Geometric “Integration” (Converting Velocity data to Spacetime)
Fig. 4.6a-bin Unit 1
Until you specifyinitial conditions y0(t0)…
...you don’t know whichvy-lines to use
initial conditions y1(0)
...and y2(0)
24Friday, August 28, 2015
Ceiling at y=7.1
Time
t-axis
Height
y-axisVy1
Vy2
1.0
1.0
-1.0
0.5
Velocity Vy2vs. V
y1Plot
Position y vs. Time t Plot
Vy1=+1.0
Vy2=-0.5
means M1is
somewhere
on some path of slope +1.0
slope
1/1=+11
1
slope
-0.5/1=-0.5-0.5
1means M
2is
somewhere
on some path of slope -0.5
Floor at y=0
-0.5
1
y
-0.5
+1.0
Bang-2(12)
position
Ceiling at y=7
Time
t-axis
Height
y-axis
slope
-1
slope
+1
Bang-1(01)
position
y2(0)=3
Vy1
Vy2
1.0
-1.0
0.5
(Vy1,Vy2)=(+1.0,-1.0)
y
(a) Vy2vs. V
y1Plot of Bang-1
(01) (b) y vs. t Plot of Bang-1(01)
Bang-1(01) Bounces (-1,-1) to (+1,-1)
(Vy1,Vy2)=(-1.0,-1.0)
(y=1,t=2)(y=0,t=1)
y1(0)=1
0.5
-1.0 -0.5
-0.5
??
??Floor at y=0
Geometric “Integration” (Converting Velocity data to Spacetime)
Fig. 4.6a-bin Unit 1
Until you specifyinitial conditions y0(t0)…
...you don’t know whichvy-lines to use
initial conditions y1(0)
...and y2(0)
25Friday, August 28, 2015
Geometric “Integration” (Converting Velocity data to Spacetime)
Start at
(-1.0,-1.0)
1.0
1.0
-1.0
0.5
2.0
Bang-2(12)
Bang-3(20)
Bang-1(01)
Floor at y=0
Bang-1(01)
Bang-2(12)
Bang-3(20)
M2
slope
+2.5
M1
slope
+0.5
Height y
y=3
y=1
Ceiling at y=7
Bang-4(12)
??
Vy1
Vy2
??
(a)
Time t
(b)
M2
slope
-2.5
26Friday, August 28, 2015
Geometric “Integration” (Converting Velocity data to Spacetime)
Start at
(-1.0,-1.0)
1.0
1.0
-1.0
0.5
2.0
Bang-2(12)
Bang-3(20)
Bang-1(01)
Floor at y=0
Bang-1(01)
Bang-2(12)
Bang-3(20)
M2
slope
+2.5
M1
slope
+0.5
Height y
y=3
y=1
Ceiling at y=7
Bang-4(12)
??
Vy1
Vy2
??
(a)
Time t Bang-1(01)
Bang-2(12)
Bang-3(20)
Bang-4(12)
Bang-5(20)
Bang-6(12)
Bang-7(01)
Bang-8(20)
Bang-9(12)
Time t
Floor at y=0
Ceiling at y=7
y
Start at
(-1.0,-1.0)
1.0
1.0
-1.0
0.5
2.0
Bang-2(12)
Bang-3(20)
Bang-4(12)
Bang-1(01)
Bang-5(20)
Bang-6(12)
Bang-7(01)
Vy1
Vy2
(b)
(c)
(d)
M2
slope
-2.5
Fig. 4.7a-din Unit 1
Kinetic Energy Ellipse
KE = 12
M1V12 + 1
2M 2V2
2 =12
+ 72= 4
1 = V12
2KE /M1
+V2
2
2KE /M 2
=x1
2
a12 +
x22
a22
27Friday, August 28, 2015
Geometric “Integration” (Converting Velocity data to Spacetime)
Start at
(-1.0,-1.0)
1.0
1.0
-1.0
0.5
2.0
Bang-2(12)
Bang-3(20)
Bang-1(01)
Floor at y=0
Bang-1(01)
Bang-2(12)
Bang-3(20)
M2
slope
+2.5
M1
slope
+0.5
Height y
y=3
y=1
Ceiling at y=7
Bang-4(12)
??
Vy1
Vy2
??
(a)
Time t Bang-1(01)
Bang-2(12)
Bang-3(20)
Bang-4(12)
Bang-5(20)
Bang-6(12)
Bang-7(01)
Bang-8(20)
Bang-9(12)
Time t
Floor at y=0
Ceiling at y=7
y
Start at
(-1.0,-1.0)
1.0
1.0
-1.0
0.5
2.0
Bang-2(12)
Bang-3(20)
Bang-4(12)
Bang-1(01)
Bang-5(20)
Bang-6(12)
Bang-7(01)
Vy1
Vy2
(b)
(c)
(d)
M2
slope
-2.5
Fig. 4.7a-din Unit 1
Kinetic Energy Ellipse
KE = 12
M1V12 + 1
2M 2V2
2 =72
+ 12= 4
1 = V12
2KE /M1
+V2
2
2KE /M 2
=x1
2
a12 +
x22
a22
Ellipse radius 1
a1 = 2KE /M1
Ellipse radius 2
a2 = 2KE /M1
28Friday, August 28, 2015
Geometric “Integration” (Converting Velocity data to Spacetime)
Start at
(-1.0,-1.0)
1.0
1.0
-1.0
0.5
2.0
Bang-2(12)
Bang-3(20)
Bang-1(01)
Floor at y=0
Bang-1(01)
Bang-2(12)
Bang-3(20)
M2
slope
+2.5
M1
slope
+0.5
Height y
y=3
y=1
Ceiling at y=7
Bang-4(12)
??
Vy1
Vy2
??
(a)
Time t Bang-1(01)
Bang-2(12)
Bang-3(20)
Bang-4(12)
Bang-5(20)
Bang-6(12)
Bang-7(01)
Bang-8(20)
Bang-9(12)
Time t
Floor at y=0
Ceiling at y=7
y
Start at
(-1.0,-1.0)
1.0
1.0
-1.0
0.5
2.0
Bang-2(12)
Bang-3(20)
Bang-4(12)
Bang-1(01)
Bang-5(20)
Bang-6(12)
Bang-7(01)
Vy1
Vy2
(b)
(c)
(d)
M2
slope
-2.5
Fig. 4.7a-din Unit 1
Kinetic Energy Ellipse
KE = 12
M1V12 + 1
2M 2V2
2 =72
+ 12= 4
1 = V12
2KE /M1
+V2
2
2KE /M 2
=x1
2
a12 +
x22
a22
Ellipse radius 1
a1 = 2KE /M1
= 2KE /7
= 8/7 = 1.07
Ellipse radius 2
a2 = 2KE /M1
= 2KE /1
= 8/1 = 2.83
29Friday, August 28, 2015
Geometric “Integration” (Converting Velocity data to Spacetime)
27825
Start Start
∞ ?
Start
4PenV2
BallV1
ErgodicFill-inat t=∞ ?
(a) (b) (c)
Fig. 4.9in Unit 1
Fig. 4.8in Unit 1
30Friday, August 28, 2015
Geometry of X2 launcher bouncing in boxIndependent Bounce Model (IBM)Geometric optimization and range-of-motion calculation(t)Integration of (V1,V2) data to space-time plots (y1(t),t) and (y2(t),t) plotsIntegration of (V1,V2) data to space-space plots (y1, y2)
31Friday, August 28, 2015
v(2)
Bang-1(01)
Start0 at
(y1(0)=1,y2(0)=3)
v(0)v(1)
Collisionliney 2=y 1
1.0
1.0
-1.0
0.5
2.0
Bang-2(12)
m2
Velocity axis
Vym2
m1
Velocity axis
Vym1
m1-Height
y1-axis
Ceilingaty1=7
Floor at y2=0.0
Flooraty1=0.0
1.0 2.0 3.0 4.0 5.0 6.0
1.0
2.0
3.0
4.0
5.0
6.0
Ceiling at y2=7
m2-Height
y2-axis
Bang-2(12)Bang-1(01)
Start0 at
(V1(0)=1, V2(0)=3)
v(1)v(0)
v(2)
Step-0: At starting position y(0)=(1,3) draw initial velocity v(0)=(-1,-1) line.Step-1: Extend v(0) line to floor point y(0)=(0,?) and draw Bang-1
(01)
velocity v(1)=(1,-1) line. (Find v(1) using V-V plot.)Step-2: Extend v(1) line to collision point y(0)=(?,?) and draw Bang-2
(12)
velocity v(2)=(0.5,2.5). (Find v(2) using V-V plot.)
Geometric “Integration” (Converting Velocity data to Space-space trajectory)
Fig. 4.11in Unit 1
32Friday, August 28, 2015
Bang-1(01)
Start0 at
(y1(0)=1,y2(0)=3)
Collisionliney 2=y 1
Bang-2(12)
Bang-3(20)
v(3)
v(4)
Bang-4(12)
v(2)
m2-Height
y2-axis
Ceiling at y2=7.1
v(5)
Bang-5(20)
Bang-6(12)
v(3)
v(4)
m1
Velocity axis
Vym1
Ceilingaty1=7.1
Floor at y2=0.0
Flooraty1=0.0
1.0 2.0 3.0 4.0 5.0 6.0
1.0
2.0
3.0
4.0
5.0
6.0
m1-Height
y1-axis
Step-2: Extend v(2) line to ceiling point y(3)=(?,7.1) and draw Bang-3(20)
velocity v(3)=(1,-1) line. (Find v(3) using V-V plot.)Step-3: Extend v(3) line to collision point y(4)=(?,?) and draw Bang-4
(12)
velocity v(4)=(0.5,2.5). (Find v(4) using V-V plot.)
Start at
(-1.0,-1.0)
1.0
1.0
-1.0
0.5
2.0
Bang-2(12)
Bang-3(20)
Bang-4(12)
m2 Velocity axis
Vym2
Step-5: Extend v(5) line to collision point y(6)=(?,?) and draw Bang-6(12)
velocity v(6)=(0.5,2.5). (Find v(6) using V-V plot.)
Step-4: Extend v(4) line to ceiling point y(4)=(?,7.1) and draw Bang-5(20)
velocity v(5)=(1,-1) line. (Find v(5) using V-V plot.)
v(5)
Geometric “Integration” (Converting Velocity data to Space-space trajectory)
Fig. 4.11in Unit 1
33Friday, August 28, 2015
Geometric “Integration” (Converting Velocity data to Space-time trajectory)
Start at(1.0,-1.0)
1.0
1.0
-1.0
2.0
3.0
4.0
5.0
6.0
7.0
-2.0
-3.0
-4.0
-5.0
-6.0
Bang-1(01)
Bang-1(01)
Bang-2(12)
Bang-4(12)
Bang-6(12)
m2 Velocity axisVym2
m1 Velocity axis Vym1
81012 14
16
18
7 9 111315 17 19
Bang-2(12)
Bang-3(20)
Bang-4(12)
Bang-6(12)
810
12
5
7
9
5
-5
Bang-3(20)
m1 = 49
m2 = 1
1113
Fig. 5.1in Unit 1
Example with masses: m1=49 and m2=1
34Friday, August 28, 2015
Geometric “Integration” (Converting Velocity data to Space-time trajectory)
Start at(1.0,-1.0)
1.0
1.0
-1.0
2.0
3.0
4.0
5.0
6.0
7.0
-2.0
-3.0
-4.0
-5.0
-6.0
Bang-1(01)
Bang-1(01)
Bang-2(12)
Bang-4(12)
Bang-6(12)
m2 Velocity axisVym2
m1 Velocity axis Vym1
81012 14
16
18
7 9 111315 17 19
Bang-2(12)
Bang-3(20)
Bang-4(12)
Bang-6(12)
810
12
5
7
9
5
-5
Bang-3(20)
m1 = 49
m2 = 1
1113
Fig. 5.1in Unit 1
Example with masses: m1=49 and m2=1Kinetic Energy Ellipse
KE = 12
m1V12 + 1
2m2V2
2 =492
+ 12= 25
1 = V12
2KE /m1
+V2
2
2KE /m2
=x1
2
a12 +
x22
a22
Ellipse radius 1
a1 = 2KE /M1
= 2KE /49
= 50/49 = 1.01
Ellipse radius 2
a2 = 2KE /m2
= 2KE /1
= 50/1 = 7.07
35Friday, August 28, 2015
Multiple collisions calculated by matrix operator products Matrix or tensor algebra of 1-D 2-body collisions“Mass-bang” matrix M, “Floor-bang” matrix F, “Ceiling-bang” matrix C.Geometry and algebra of “ellipse-Rotation” group product: R= C•M
36Friday, August 28, 2015
Multiple Collisions by Matrix Operator Products
v1FIN
v2FIN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
2VCOM − v1IN
2VCOM − v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
T-Symmetry & Momentum Axioms give: VCOM = VFIN +V IN
2= m1v1 +m2v2
m1 +m2
Gives vFIN in terms of vIN...
2 m1v1IN +m2v2
IN
m1 +m2
− v1IN
2 m1v1IN +m2v2
IN
m1 +m2
− v2IN
⎛
⎝
⎜⎜⎜⎜⎜
⎞
⎠
⎟⎟⎟⎟⎟
=
m1v1IN −m2v1
IN + 2m2v2IN
2m1v1IN +m2v2
IN −m1v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
=
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
v1IN
v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
Finally as a matrix operation: vFIN =M•vIN...
M =
m1 −m2
m1 +m2
2m2
m1 +m2
2m1
m1 +m2
m2 −m1
m1 +m2
⎛
⎝
⎜⎜⎜⎜⎜
⎞
⎠
⎟⎟⎟⎟⎟
Matrix operations include...Floor bounce F of m1: Mass collision M of m1 and m2 : Ceiling bounce C of m2:
F = −1 00 1
⎛⎝⎜
⎞⎠⎟
C = 1 00 −1
⎛⎝⎜
⎞⎠⎟
Let: m1=49 and m2=1 M = 0.96 0.041.96 −0.96
⎛⎝⎜
⎞⎠⎟
Define a “rotation” R as group product: R= C•M = 1 00 −1
⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.041.96 −0.96
⎛⎝⎜
⎞⎠⎟= 0.96 0.04
−1.96 0.96⎛⎝⎜
⎞⎠⎟
37Friday, August 28, 2015
Multiple Collisions by Matrix Operator Products
v1FIN
v2FIN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
2VCOM − v1IN
2VCOM − v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
T-Symmetry & Momentum Axioms give: VCOM = VFIN +V IN
2= m1v1 +m2v2
m1 +m2
Gives vFIN in terms of vIN...
2 m1v1IN +m2v2
IN
m1 +m2
− v1IN
2 m1v1IN +m2v2
IN
m1 +m2
− v2IN
⎛
⎝
⎜⎜⎜⎜⎜
⎞
⎠
⎟⎟⎟⎟⎟
=
m1v1IN −m2v1
IN + 2m2v2IN
2m1v1IN +m2v2
IN −m1v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
=
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
v1IN
v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
Finally as a matrix operation: vFIN =M•vIN...
Matrix operations include...Floor bounce F of m1: Mass collision M of m1 and m2 : Ceiling bounce C of m2:
Let: m1=49 and m2=1
Define a “rotation” R as group product: R= C•M
38Friday, August 28, 2015
Multiple Collisions by Matrix Operator Products
v1FIN
v2FIN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
2VCOM − v1IN
2VCOM − v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
T-Symmetry & Momentum Axioms give: VCOM = VFIN +V IN
2= m1v1 +m2v2
m1 +m2
Gives vFIN in terms of vIN...
2 m1v1IN +m2v2
IN
m1 +m2
− v1IN
2 m1v1IN +m2v2
IN
m1 +m2
− v2IN
⎛
⎝
⎜⎜⎜⎜⎜
⎞
⎠
⎟⎟⎟⎟⎟
=
m1v1IN −m2v1
IN + 2m2v2IN
2m1v1IN +m2v2
IN −m1v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
=
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
v1IN
v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
Finally as a matrix operation: vFIN =M•vIN...
Matrix operations include...Floor bounce F of m1: Mass collision M of m1 and m2 : Ceiling bounce C of m2:
Let: m1=49 and m2=1
Define a “rotation” R as group product: R= C•M
39Friday, August 28, 2015
Multiple Collisions by Matrix Operator Products
v1FIN
v2FIN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
2VCOM − v1IN
2VCOM − v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
T-Symmetry & Momentum Axioms give: VCOM = VFIN +V IN
2= m1v1 +m2v2
m1 +m2
Gives vFIN in terms of vIN...
2 m1v1IN +m2v2
IN
m1 +m2
− v1IN
2 m1v1IN +m2v2
IN
m1 +m2
− v2IN
⎛
⎝
⎜⎜⎜⎜⎜
⎞
⎠
⎟⎟⎟⎟⎟
=
m1v1IN −m2v1
IN + 2m2v2IN
2m1v1IN +m2v2
IN −m1v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
=
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
v1IN
v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
Finally as a matrix operation: vFIN =M•vIN...
M =
m1 −m2
m1 +m2
2m2
m1 +m2
2m1
m1 +m2
m2 −m1
m1 +m2
⎛
⎝
⎜⎜⎜⎜⎜
⎞
⎠
⎟⎟⎟⎟⎟
Matrix operations include...Floor bounce F of m1: Mass collision M of m1 and m2 : Ceiling bounce C of m2:
F = −1 00 1
⎛⎝⎜
⎞⎠⎟
C = 1 00 −1
⎛⎝⎜
⎞⎠⎟
Let: m1=49 and m2=1 M = 0.96 0.041.96 −0.96
⎛⎝⎜
⎞⎠⎟
Define a “rotation” R as group product: R= C•M = 1 00 −1
⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.041.96 −0.96
⎛⎝⎜
⎞⎠⎟= 0.96 0.04
−1.96 0.96⎛⎝⎜
⎞⎠⎟
40Friday, August 28, 2015
Multiple collisions calculated by matrix operator products Matrix or tensor algebra of 1-D 2-body collisions“Mass-bang” matrix M, “Floor-bang” matrix F, “Ceiling-bang” matrix C.Geometry and algebra of “ellipse-Rotation” group product: R= C•M
41Friday, August 28, 2015
Multiple Collisions by Matrix Operator Products
v1FIN
v2FIN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
2VCOM − v1IN
2VCOM − v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
T-Symmetry & Momentum Axioms give: VCOM = VFIN +V IN
2= m1v1 +m2v2
m1 +m2
Gives vFIN in terms of vIN...
2 m1v1IN +m2v2
IN
m1 +m2
− v1IN
2 m1v1IN +m2v2
IN
m1 +m2
− v2IN
⎛
⎝
⎜⎜⎜⎜⎜
⎞
⎠
⎟⎟⎟⎟⎟
=
m1v1IN −m2v1
IN + 2m2v2IN
2m1v1IN +m2v2
IN −m1v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
=
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
v1IN
v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
Finally as a matrix operation: vFIN =M•vIN...
Matrix operations include...Floor-bang F of m1:
F = −1 00 1
⎛⎝⎜
⎞⎠⎟
Define a “rotation” R as group product: R= C•M
42Friday, August 28, 2015
Multiple Collisions by Matrix Operator Products
v1FIN
v2FIN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
2VCOM − v1IN
2VCOM − v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
T-Symmetry & Momentum Axioms give: VCOM = VFIN +V IN
2= m1v1 +m2v2
m1 +m2
Gives vFIN in terms of vIN...
2 m1v1IN +m2v2
IN
m1 +m2
− v1IN
2 m1v1IN +m2v2
IN
m1 +m2
− v2IN
⎛
⎝
⎜⎜⎜⎜⎜
⎞
⎠
⎟⎟⎟⎟⎟
=
m1v1IN −m2v1
IN + 2m2v2IN
2m1v1IN +m2v2
IN −m1v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
=
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
v1IN
v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
Finally as a matrix operation: vFIN =M•vIN...
Matrix operations include...Floor-bang F of m1: Ceiling-bang C of m2:
F = −1 00 1
⎛⎝⎜
⎞⎠⎟
C = 1 00 −1
⎛⎝⎜
⎞⎠⎟
Define a “rotation” R as group product: R= C•M
43Friday, August 28, 2015
Multiple Collisions by Matrix Operator Products
v1FIN
v2FIN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
2VCOM − v1IN
2VCOM − v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
T-Symmetry & Momentum Axioms give: VCOM = VFIN +V IN
2= m1v1 +m2v2
m1 +m2
Gives vFIN in terms of vIN...
2 m1v1IN +m2v2
IN
m1 +m2
− v1IN
2 m1v1IN +m2v2
IN
m1 +m2
− v2IN
⎛
⎝
⎜⎜⎜⎜⎜
⎞
⎠
⎟⎟⎟⎟⎟
=
m1v1IN −m2v1
IN + 2m2v2IN
2m1v1IN +m2v2
IN −m1v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
=
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
v1IN
v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
Finally as a matrix operation: vFIN =M•vIN...
M =
m1 −m2
m1 +m2
2m2
m1 +m2
2m1
m1 +m2
m2 −m1
m1 +m2
⎛
⎝
⎜⎜⎜⎜⎜
⎞
⎠
⎟⎟⎟⎟⎟
Matrix operations include...Floor-bang F of m1: Mass-bang M of m1 and m2 : Ceiling-bang C of m2:
F = −1 00 1
⎛⎝⎜
⎞⎠⎟
C = 1 00 −1
⎛⎝⎜
⎞⎠⎟
Define a “rotation” R as group product: R= C•M
44Friday, August 28, 2015
Multiple Collisions by Matrix Operator Products
v1FIN
v2FIN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
2VCOM − v1IN
2VCOM − v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
T-Symmetry & Momentum Axioms give: VCOM = VFIN +V IN
2= m1v1 +m2v2
m1 +m2
Gives vFIN in terms of vIN...
2 m1v1IN +m2v2
IN
m1 +m2
− v1IN
2 m1v1IN +m2v2
IN
m1 +m2
− v2IN
⎛
⎝
⎜⎜⎜⎜⎜
⎞
⎠
⎟⎟⎟⎟⎟
=
m1v1IN −m2v1
IN + 2m2v2IN
2m1v1IN +m2v2
IN −m1v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
=
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
v1IN
v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
Finally as a matrix operation: vFIN =M•vIN...
M =
m1 −m2
m1 +m2
2m2
m1 +m2
2m1
m1 +m2
m2 −m1
m1 +m2
⎛
⎝
⎜⎜⎜⎜⎜
⎞
⎠
⎟⎟⎟⎟⎟
Matrix operations include...Floor-bang F of m1: Mass-bang M of m1 and m2 : Ceiling-bang C of m2:
F = −1 00 1
⎛⎝⎜
⎞⎠⎟
C = 1 00 −1
⎛⎝⎜
⎞⎠⎟
Let: m1=49 and m2=1 M = 0.96 0.041.96 −0.96
⎛⎝⎜
⎞⎠⎟
Define a “rotation” R as group product: R= C•M = 1 00 −1
⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.041.96 −0.96
⎛⎝⎜
⎞⎠⎟= 0.96 0.04
−1.96 0.96⎛⎝⎜
⎞⎠⎟
45Friday, August 28, 2015
Multiple collisions calculated by matrix operator products Matrix or tensor algebra of 1-D 2-body collisions“Mass-bang” matrix M, “Floor-bang” matrix F, “Ceiling-bang” matrix C.Geometry and algebra of “ellipse-Rotation” group product: R= C•M
46Friday, August 28, 2015
Multiple Collisions by Matrix Operator Products
v1FIN
v2FIN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
2VCOM − v1IN
2VCOM − v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟=
T-Symmetry & Momentum Axioms give: VCOM = VFIN +V IN
2= m1v1 +m2v2
m1 +m2
Gives vFIN in terms of vIN...
2 m1v1IN +m2v2
IN
m1 +m2
− v1IN
2 m1v1IN +m2v2
IN
m1 +m2
− v2IN
⎛
⎝
⎜⎜⎜⎜⎜
⎞
⎠
⎟⎟⎟⎟⎟
=
m1v1IN −m2v1
IN + 2m2v2IN
2m1v1IN +m2v2
IN −m1v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
=
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
v1IN
v2IN
⎛
⎝⎜⎜
⎞
⎠⎟⎟
m1 +m2
Finally as a matrix operation: vFIN =M•vIN...
M =
m1 −m2
m1 +m2
2m2
m1 +m2
2m1
m1 +m2
m2 −m1
m1 +m2
⎛
⎝
⎜⎜⎜⎜⎜
⎞
⎠
⎟⎟⎟⎟⎟
Matrix operations include...Floor-bang F of m1: Mass-bang M of m1 and m2 : Ceiling-bang C of m2:
F = −1 00 1
⎛⎝⎜
⎞⎠⎟
C = 1 00 −1
⎛⎝⎜
⎞⎠⎟
Let: m1=49 and m2=1 M = 0.96 0.041.96 −0.96
⎛⎝⎜
⎞⎠⎟
Define “ellipse-Rotation” R as group product: R= C•M= 1 00 −1
⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.041.96 −0.96
⎛⎝⎜
⎞⎠⎟= 0.96 0.04
−1.96 0.96⎛⎝⎜
⎞⎠⎟
47Friday, August 28, 2015
C • M • C • M • C • M • C • M • F IN 0FIN 9 =
v1FIN−9
v2FIN−9
⎛
⎝⎜⎜
⎞
⎠⎟⎟= 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ −1 0
0 +1⎛⎝⎜
⎞⎠⎟
v1IN = −1
v2IN = −1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
INITIAL (0)( )
48Friday, August 28, 2015
C • M • C • M • C • M • C • M • F
v1FIN−9
v2FIN−9
⎛
⎝⎜⎜
⎞
⎠⎟⎟= 0.96 0.04
−1.96 0.96⎛⎝⎜
⎞⎠⎟
⋅ 0.96 0.04−1.96 0.96
⎛⎝⎜
⎞⎠⎟
⋅ 0.96 0.04−1.96 0.96
⎛⎝⎜
⎞⎠⎟
⋅ 0.96 0.04−1.96 0.96
⎛⎝⎜
⎞⎠⎟
⋅v1 = 1v2 = −1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
after Bang-1( )
R • R • R • R • F
IN 0
IN 0FIN 9 =
FIN 9 =
v1FIN−9
v2FIN−9
⎛
⎝⎜⎜
⎞
⎠⎟⎟= 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ −1 0
0 +1⎛⎝⎜
⎞⎠⎟
v1IN = −1
v2IN = −1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
INITIAL (0)( )
“ellipse-Rotation” group product: R= C•M
49Friday, August 28, 2015
C • M • C • M • C • M • C • M • F
v1FIN−9
v2FIN−9
⎛
⎝⎜⎜
⎞
⎠⎟⎟= 0.96 0.04
−1.96 0.96⎛⎝⎜
⎞⎠⎟
⋅ 0.96 0.04−1.96 0.96
⎛⎝⎜
⎞⎠⎟
⋅ 0.96 0.04−1.96 0.96
⎛⎝⎜
⎞⎠⎟
⋅ 0.96 0.04−1.96 0.96
⎛⎝⎜
⎞⎠⎟
⋅v1 = 1v2 = −1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
after Bang-1( )
=v1 = 0.2925v2 = −6.768
⎛
⎝⎜⎜
⎞
⎠⎟⎟
after Bang-9( )
R • R • R • R • F
IN 0
IN 0FIN 9 =
FIN 9 =
v1FIN−9
v2FIN−9
⎛
⎝⎜⎜
⎞
⎠⎟⎟= 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ −1 0
0 +1⎛⎝⎜
⎞⎠⎟
v1IN = −1
v2IN = −1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
INITIAL (0)( )
“ellipse-Rotation” group product: R= C•M
50Friday, August 28, 2015
Start at(1.0,-1.0)
1.0
1.0
-1.0
2.0
3.0
4.0
5.0
6.0
7.0
-2.0
-3.0
-4.0
-5.0
-6.0
Bang-1(01)
Bang-1(01)
Bang-2(12)
Bang-4(12)
Bang-6(12)
m2 Velocity axisVym2
m1 Velocity axis Vym1
81012 14
16
18
7 9 111315 17 19
Bang-2(12)
Bang-3(20)
Bang-4(12)
Bang-6(12)
810
12
5
7
9
5
-5
Bang-3(20)
m1 = 49
m2 = 1
1113
C • M • C • M • C • M • C • M • F
v1FIN−9
v2FIN−9
⎛
⎝⎜⎜
⎞
⎠⎟⎟= 0.96 0.04
−1.96 0.96⎛⎝⎜
⎞⎠⎟
⋅ 0.96 0.04−1.96 0.96
⎛⎝⎜
⎞⎠⎟
⋅ 0.96 0.04−1.96 0.96
⎛⎝⎜
⎞⎠⎟
⋅ 0.96 0.04−1.96 0.96
⎛⎝⎜
⎞⎠⎟
⋅v1 = 1v2 = −1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
after Bang-1( )
=v1 = 0.2925v2 = −6.768
⎛
⎝⎜⎜
⎞
⎠⎟⎟
after Bang-9( )
R • R • R • R • F
IN 0
IN 0FIN 9 =
FIN 9 =
v1FIN−9
v2FIN−9
⎛
⎝⎜⎜
⎞
⎠⎟⎟= 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ −1 0
0 +1⎛⎝⎜
⎞⎠⎟
v1IN = −1
v2IN = −1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
INITIAL (0)( )
R
R
R
R
F
“ellipse-Rotation” group product: R= C•M
51Friday, August 28, 2015
Start at(1.0,-1.0)
1.0
1.0
-1.0
2.0
3.0
4.0
5.0
6.0
7.0
-2.0
-3.0
-4.0
-5.0
-6.0
Bang-1(01)
Bang-1(01)
Bang-2(12)
Bang-4(12)
Bang-6(12)
m2 Velocity axisVym2
m1 Velocity axis Vym1
81012 14
16
18
7 9 111315 17 19
Bang-2(12)
Bang-3(20)
Bang-4(12)
Bang-6(12)
810
12
5
7
9
5
-5
Bang-3(20)
m1 = 49
m2 = 1
1113
C • M • C • M • C • M • C • M • F
v1FIN−9
v2FIN−9
⎛
⎝⎜⎜
⎞
⎠⎟⎟= 0.96 0.04
−1.96 0.96⎛⎝⎜
⎞⎠⎟
⋅ 0.96 0.04−1.96 0.96
⎛⎝⎜
⎞⎠⎟
⋅ 0.96 0.04−1.96 0.96
⎛⎝⎜
⎞⎠⎟
⋅ 0.96 0.04−1.96 0.96
⎛⎝⎜
⎞⎠⎟
⋅v1 = 1v2 = −1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
after Bang-1( )
=v1 = 0.2925v2 = −6.768
⎛
⎝⎜⎜
⎞
⎠⎟⎟
after Bang-9( )
R • R • R • R • F
IN 0
IN 0FIN 9 =
FIN 9 =
v1FIN−9
v2FIN−9
⎛
⎝⎜⎜
⎞
⎠⎟⎟= 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ 1 0
0 −1⎛⎝⎜
⎞⎠⎟⋅ 0.96 0.04
1.96 −0.96⎛⎝⎜
⎞⎠⎟⋅ −1 0
0 +1⎛⎝⎜
⎞⎠⎟
v1IN = −1
v2IN = −1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
INITIAL (0)( )
R
R
R
R
F
v1FIN−11
v2FIN−11
⎛
⎝⎜⎜
⎞
⎠⎟⎟= 0.96 0.04
−1.96 0.96⎛⎝⎜
⎞⎠⎟⋅
v1FIN−9
v2FIN−9
⎛
⎝⎜⎜
⎞
⎠⎟⎟
=v1 = 0.0100v2 = −7.071
⎛
⎝⎜⎜
⎞
⎠⎟⎟
after Bang-11( )
“ellipse-Rotation” group product: R= C•M
52Friday, August 28, 2015
Ellipse rescaling-geometry and reflection-symmetry analysisRescaling KE ellipse to circle
How this relates to Lagrangian, l’Etrangian, and Hamiltonian mechanics in Ch. 12
53Friday, August 28, 2015
Ellipse rescaling geometry and reflection symmetry analysis Convert to rescaled velocity: symmetrize: V1 = v1 ⋅ m1 , V2 = v2 ⋅ m1 , KE =2
1m1v12+2
1m2v22 =2
1 V12 +21 V22
11
33
77
1177
1199
11331155
55
991111
2211
v1
v2
slope1/1
slope-1/1
[11]-tangentslope
-m1/m2= -49
22
44
54Friday, August 28, 2015
Ellipse rescaling geometry and reflection symmetry analysis Convert to rescaled velocity: symmetrize: V1 = v1 ⋅ m1 , V2 = v2 ⋅ m1 , KE =2
1m1v12+2
1m2v22 =2
1 V12 +21 V22
v1FIN1
v2FIN1
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟= 1M
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
v1v2
⎛
⎝⎜⎜
⎞
⎠⎟⎟
becomes: V1FIN1 / m1
V2FIN1 / m2
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟ =
1M
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
V1 / m1
V2 / m2
⎛
⎝⎜⎜
⎞
⎠⎟⎟
11
33
77
1177
1199
11331155
55
991111
2211
v1
v2
slope1/1
slope-1/1
[11]-tangentslope
-m1/m2= -49
22
44
55Friday, August 28, 2015
Ellipse rescaling geometry and reflection symmetry analysis Convert to rescaled velocity: symmetrize: V1 = v1 ⋅ m1 , V2 = v2 ⋅ m1 , KE =2
1m1v12+2
1m2v22 =2
1 V12 +21 V22
v1FIN1
v2FIN1
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟= 1M
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
v1v2
⎛
⎝⎜⎜
⎞
⎠⎟⎟
becomes: V1FIN1 / m1
V2FIN1 / m2
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟ =
1M
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
V1 / m1
V2 / m2
⎛
⎝⎜⎜
⎞
⎠⎟⎟
or: V1FIN1
V2FIN1
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟= 1M
m1 −m2 2 m1m2
2 m1m2 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
V1
V2
⎛
⎝⎜⎜
⎞
⎠⎟⎟=M i
V , or:
V1FIN2
V2FIN2
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟= 1M
m1 −m2 2 m1m2
−2 m1m2 m1 −m2
⎛
⎝⎜⎜
⎞
⎠⎟⎟
V1
V2
⎛
⎝⎜⎜
⎞
⎠⎟⎟= C iM i
V
11
33
77
1177
1199
11331155
55
991111
2211
v1
v2
slope1/1
slope-1/1
[11]-tangentslope
-m1/m2= -49
22
44
56Friday, August 28, 2015
Ellipse rescaling geometry and reflection symmetry analysis Convert to rescaled velocity: symmetrize: V1 = v1 ⋅ m1 , V2 = v2 ⋅ m1 , KE =2
1m1v12+2
1m2v22 =2
1 V12 +21 V22
v1FIN1
v2FIN1
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟= 1M
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
v1v2
⎛
⎝⎜⎜
⎞
⎠⎟⎟
becomes: V1FIN1 / m1
V2FIN1 / m2
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟ =
1M
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
V1 / m1
V2 / m2
⎛
⎝⎜⎜
⎞
⎠⎟⎟
or: V1FIN1
V2FIN1
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟= 1M
m1 −m2 2 m1m2
2 m1m2 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
V1
V2
⎛
⎝⎜⎜
⎞
⎠⎟⎟=M i
V , or:
V1FIN2
V2FIN2
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟= 1M
m1 −m2 2 m1m2
−2 m1m2 m1 −m2
⎛
⎝⎜⎜
⎞
⎠⎟⎟
V1
V2
⎛
⎝⎜⎜
⎞
⎠⎟⎟= C iM i
V
Then collisions become reflections and double-collisions become rotations
where:
cosθ sinθsinθ −cosθ
⎛
⎝⎜⎞
⎠⎟cosθ sinθ−sinθ cosθ
⎛
⎝⎜⎞
⎠⎟
cosθ ≡ m1 −m2
m1 +m2
⎛⎝⎜
⎞⎠⎟
and: sinθ ≡2 m1m2
m1 +m2
⎛
⎝⎜⎞
⎠⎟ with: m1 −m2
m1 +m2
⎛⎝⎜
⎞⎠⎟
2
+2 m1m2
m1 +m2
⎛
⎝⎜⎞
⎠⎟
2
= 1
11
33
77
1177
1199
11331155
55
991111
2211
v1
v2
slope1/1
slope-1/1
[11]-tangentslope
-m1/m2= -49
22
44
57Friday, August 28, 2015
Ellipse rescaling geometry and reflection symmetry analysis Convert to rescaled velocity: symmetrize: V1 = v1 ⋅ m1 , V2 = v2 ⋅ m1 , KE =2
1m1v12+2
1m2v22 =2
1 V12 +21 V22
v1FIN1
v2FIN1
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟= 1M
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
v1v2
⎛
⎝⎜⎜
⎞
⎠⎟⎟
becomes: V1FIN1 / m1
V2FIN1 / m2
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟ =
1M
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
V1 / m1
V2 / m2
⎛
⎝⎜⎜
⎞
⎠⎟⎟
or: V1FIN1
V2FIN1
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟= 1M
m1 −m2 2 m1m2
2 m1m2 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
V1
V2
⎛
⎝⎜⎜
⎞
⎠⎟⎟=M i
V , or:
V1FIN2
V2FIN2
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟= 1M
m1 −m2 2 m1m2
−2 m1m2 m1 −m2
⎛
⎝⎜⎜
⎞
⎠⎟⎟
V1
V2
⎛
⎝⎜⎜
⎞
⎠⎟⎟= C iM i
V
Then collisions become reflections and double-collisions become rotations
where:
cosθ sinθsinθ −cosθ
⎛
⎝⎜⎞
⎠⎟cosθ sinθ−sinθ cosθ
⎛
⎝⎜⎞
⎠⎟
cosθ ≡ m1 −m2
m1 +m2
⎛⎝⎜
⎞⎠⎟
and: sinθ ≡2 m1m2
m1 +m2
⎛
⎝⎜⎞
⎠⎟ with: m1 −m2
m1 +m2
⎛⎝⎜
⎞⎠⎟
2
+2 m1m2
m1 +m2
⎛
⎝⎜⎞
⎠⎟
2
= 1
Fig. 5.2a-c(revised)
θ=16.26°1
m1 - m2m1+m2 2√m1 m2
m1+m2
4850=
1450=
slope :
−m2
m1
= −17
slope :
+m2
m1
= +17
11
33
77
1177
1199
11331155
55
991111
2211
θ=16.26°V1
V2
[11]-tangent slope-√m1/√m2= -7
22
44
11
33
77
1177
1199
11331155
55
991111
2211
v1
v2
slope1/1
slope-1/1
[11]-tangentslope
-m1/m2= -49
22
44
58Friday, August 28, 2015
Ellipse rescaling geometry and reflection symmetry analysis Convert to rescaled velocity: symmetrize: V1 = v1 ⋅ m1 , V2 = v2 ⋅ m1 , KE =2
1m1v12+2
1m2v22 =2
1 V12 +21 V22
v1FIN1
v2FIN1
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟= 1M
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
v1v2
⎛
⎝⎜⎜
⎞
⎠⎟⎟
becomes: V1FIN1 / m1
V2FIN1 / m2
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟ =
1M
m1 −m2 2m2
2m1 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
V1 / m1
V2 / m2
⎛
⎝⎜⎜
⎞
⎠⎟⎟
or: V1FIN1
V2FIN1
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟= 1M
m1 −m2 2 m1m2
2 m1m2 m2 −m1
⎛
⎝⎜⎜
⎞
⎠⎟⎟
V1
V2
⎛
⎝⎜⎜
⎞
⎠⎟⎟=M i
V , or:
V1FIN2
V2FIN2
⎛
⎝
⎜⎜
⎞
⎠
⎟⎟= 1M
m1 −m2 2 m1m2
−2 m1m2 m1 −m2
⎛
⎝⎜⎜
⎞
⎠⎟⎟
V1
V2
⎛
⎝⎜⎜
⎞
⎠⎟⎟= C iM i
V
Then collisions become reflections and double-collisions become rotations
where:
cosθ sinθsinθ −cosθ
⎛
⎝⎜⎞
⎠⎟cosθ sinθ−sinθ cosθ
⎛
⎝⎜⎞
⎠⎟
cosθ ≡ m1 −m2
m1 +m2
⎛⎝⎜
⎞⎠⎟
and: sinθ ≡2 m1m2
m1 +m2
⎛
⎝⎜⎞
⎠⎟ with: m1 −m2
m1 +m2
⎛⎝⎜
⎞⎠⎟
2
+2 m1m2
m1 +m2
⎛
⎝⎜⎞
⎠⎟
2
= 1
Fig. 5.2a-c(revised)
θ=16.26°1
m1 - m2m1+m2 2√m1 m2
m1+m2
4850=
1450=
slope :
−m2
m1
= −17
slope :
+m2
m1
= +17
11
33
77
1177
1199
11331155
55
991111
2211
θ=16.26°V1
V2
[11]-tangent slope-√m1/√m2= -7
22
44
11
33
77
1177
1199
11331155
55
991111
2211
v1
v2
slope1/1
slope-1/1
[11]-tangentslope
-m1/m2= -49
22
44
Note: If m1·m2 is perfect-square, then θ-triangle is rational (32+42=52, etc.)59Friday, August 28, 2015
Ellipse rescaling geometry and reflection symmetry analysis Convert to rescaled velocity: symmetrize: V1 = v1 ⋅ m1 , V2 = v2 ⋅ m1 , KE =2
1m1v12+2
1m2v22 =2
1 V12 +21 V22Then collisions become reflections and double-collisions become rotations
where:
cosθ sinθsinθ −cosθ
⎛
⎝⎜⎞
⎠⎟
cosθ ≡ m1 − m2
m1 + m2
⎛⎝⎜
⎞⎠⎟
and: sinθ ≡2 m1m2
m1 + m2
⎛
⎝⎜
⎞
⎠⎟ with: m1 − m2
m1 + m2
⎛⎝⎜
⎞⎠⎟
2
+2 m1m2
m1 + m2
⎛
⎝⎜
⎞
⎠⎟
2
= 1
Fig. 5.2a-c(revised)
θ=16.26°1
m1 - m2m1+m2 2√m1 m2
m1+m2
4850=
1450=
slope :
−m2
m1
= −17
slope :
+m2
m1
= +17
11
33
77
1177
1199
11331155
55
991111
2211
θ=16.26°V1
V2
[11]-tangent slope-√m1/√m2= -7
22
44
11
33
77
1177
1199
11331155
55
991111
2211
v1
v2
slope1/1
slope-1/1
[11]-tangentslope
-m1/m2= -49
22
44
60Friday, August 28, 2015
Fig. 5.2a-c(revised)
θ=16.26°1
m1 - m2m1+m2 2√m1 m2
m1+m2
4850=
1450=
slope :
−m2
m1
=−17
slope :
+m2
m1
=+17
11
33
77
1177
1199
11331155
55
991111
2211
v1
v2
slope1/1
slope-1/1
[11]-tangentslope
-m1/m2= -49
22
44
11
33
77
1177
1199
11331155
55
991111
2211
θ=16.26°V1
V2
[11]-tangent slope-√m1/√m2= -7
22
44
61Friday, August 28, 2015
Ellipse rescaling-geometry and reflection-symmetry analysisRescaling KE ellipse to circle
How this relates to Lagrangian, l’Etrangian, and Hamiltonian mechanics in Ch. 12
62Friday, August 28, 2015
What ellipse rescaling leads to...(in Ch. 9-12)
(a) Lagrangian L = L(v1,v2)
v1
v2(b) Estrangian E = E(V1,V2)
V1=√m1v1
(c) Hamiltonian H = H(p1,p2)
p1=m1v1
p2=m2v2
V2=√m2v2
COM Bisectorslope = 1/1
Collision line andCOM tangent slope= -m1/m2 =-16
Collision line andCOM tangent slope=-√m1/√m2=-4
COM Bisector slope= √m2/√m1 =1/4
Collision line andCOM tangent slope
= -1/1
COM Bisector slope= m2/m1 =1/16
slope√m1√m2
=4
slope=1
Fig. 12.1
How this relates to Lagrangian, l’Etrangian, and Hamiltonian mechanics in Ch. 12
velocity v1 rescaled to momentum: p1 = m1v1
velocity v2 rescaled to momentum: p2 = m2v2
63Friday, August 28, 2015
What ellipse rescaling leads to...(in Ch. 9-12)
(a) Lagrangian L = L(v1,v2)
v1
v2(b) Estrangian E = E(V1,V2)
V1=√m1v1
(c) Hamiltonian H = H(p1,p2)
p1=m1v1
p2=m2v2
V2=√m2v2
COM Bisectorslope = 1/1
Collision line andCOM tangent slope= -m1/m2 =-16
Collision line andCOM tangent slope=-√m1/√m2=-4
COM Bisector slope= √m2/√m1 =1/4
Collision line andCOM tangent slope
= -1/1
COM Bisector slope= m2/m1 =1/16
slope√m1√m2
=4
slope=1
Fig. 12.1
How this relates to Lagrangian, l’Etrangian, and Hamiltonian mechanics in Ch. 12
velocity v1 rescaled to momentum: p1 = m1v1
velocity v2 rescaled to momentum: p2 = m2v2
Lagrangian L(v1,v2 ) = KE =12m1v1
2 +12m2v2
2
rescaled to
Hamiltonian H (p1, p2 ) = KE =p1
2
2m1
+p2
2
2m2
64Friday, August 28, 2015
What ellipse rescaling leads to...(in Ch. 9-12)
(a) Lagrangian L = L(v1,v2)
v1
v2(b) Estrangian E = E(V1,V2)
V1=√m1v1
(c) Hamiltonian H = H(p1,p2)
p1=m1v1
p2=m2v2
V2=√m2v2
COM Bisectorslope = 1/1
Collision line andCOM tangent slope= -m1/m2 =-16
Collision line andCOM tangent slope=-√m1/√m2=-4
COM Bisector slope= √m2/√m1 =1/4
Collision line andCOM tangent slope
= -1/1
COM Bisector slope= m2/m1 =1/16
slope√m1√m2
=4
slope=1
Fig. 12.1
(Now we call this one “l’Etrangian”)
How this relates to Lagrangian, l’Etrangian, and Hamiltonian mechanics in Ch. 12
65Friday, August 28, 2015
Ellipse rescaling-geometry and reflection-symmetry analysisRescaling KE ellipse to circle
How this relates to Lagrangian, l’Etrangian, and Hamiltonian mechanics in Ch. 12(Preview of Lecture 3)
Reflections in the clothing store: “It’s all done with mirrors!” Introducing hexagonal symmetry D6~C6v (Resulting for m1/m2=3)
Group multiplication and product tableClassical collision paths with D6~C6v (Resulting from m1/m2=3)
66Friday, August 28, 2015
Reflections in clothing store mirrors
Fig. 5.4a-b
67Friday, August 28, 2015
σφacts1st
σφacts2nd
(a)Reflections σA=( ),
x=σA·x=( )10
y=( )01
-y=( )=σA·y
-10
1 00 -1 -σA=( )-1 0
0 1
y=( ) = -σA·y01
10
-x=( )= -σA·x
-10
x=( )
(c) σφ reflection ( )of x-vector: ...of y-vector:
σφ·x=( )ycosφsinφ
cosφ sinφsinφ -cosφ
xφ/2
φ/2
σφ·y=( )sinφ-cosφ
y
xφ/2
φ/2φ
φ -cosφsinφ
cosφ
sinφ
(b)Reflections σB=( ),
x=( )=σB·y
10
y=( ) =σB·x01
0 11 0 -σB=( )
-y=( )= -σB·x
0-1
y=( )01
0 -1-1 0
-x=( )= -σB·y
-10
Mirror plane(edge-on)
(d)Rotation:R+φ=σφσA=( ) (e)Rotation:R−φ=σAσφ=( )cosφ -sinφsinφ cosφ
cosφ sinφ- sinφ cosφy
xφ/2
φ/2
y
xφ/2
φ/2
σA·y
σA·xσφ·y
σφ·x
φ/2
φ/2
σA acts1st
σA acts2nd
+φ y
x
−φ
−φ
Symmetry: It’s all done with mirrors!
Fig. 5.3a-e
68Friday, August 28, 2015
σφacts1st
σφacts2nd
(a)Reflections σA=( ),
x=σA·x=( )10
y=( )01
-y=( )=σA·y
-10
1 00 -1 -σA=( )-1 0
0 1
y=( ) = -σA·y01
10
-x=( )= -σA·x
-10
x=( )
(c) σφ reflection ( )of x-vector: ...of y-vector:
σφ·x=( )ycosφsinφ
cosφ sinφsinφ -cosφ
xφ/2
φ/2
σφ·y=( )sinφ-cosφ
y
xφ/2
φ/2φ
φ -cosφsinφ
cosφ
sinφ
(b)Reflections σB=( ),
x=( )=σB·y
10
y=( ) =σB·x01
0 11 0 -σB=( )
-y=( )= -σB·x
0-1
y=( )01
0 -1-1 0
-x=( )= -σB·y
-10
Mirror plane(edge-on)
(d)Rotation:R+φ=σφσA=( ) (e)Rotation:R−φ=σAσφ=( )cosφ -sinφsinφ cosφ
cosφ sinφ- sinφ cosφy
xφ/2
φ/2
y
xφ/2
φ/2
σA·y
σA·xσφ·y
σφ·x
φ/2
φ/2
σA acts1st
σA acts2nd
+φ y
x
−φ
−φ
Symmetry: It’s all done with mirrors!
Fig. 5.3a-e
69Friday, August 28, 2015
σφacts1st
σφacts2nd
(a)Reflections σA=( ),
x=σA·x=( )10
y=( )01
-y=( )=σA·y
-10
1 00 -1 -σA=( )-1 0
0 1
y=( ) = -σA·y01
10
-x=( )= -σA·x
-10
x=( )
(c) σφ reflection ( )of x-vector: ...of y-vector:
σφ·x=( )ycosφsinφ
cosφ sinφsinφ -cosφ
xφ/2
φ/2
σφ·y=( )sinφ-cosφ
y
xφ/2
φ/2φ
φ -cosφsinφ
cosφ
sinφ
(b)Reflections σB=( ),
x=( )=σB·y
10
y=( ) =σB·x01
0 11 0 -σB=( )
-y=( )= -σB·x
0-1
y=( )01
0 -1-1 0
-x=( )= -σB·y
-10
Mirror plane(edge-on)
(d)Rotation:R+φ=σφσA=( ) (e)Rotation:R−φ=σAσφ=( )cosφ -sinφsinφ cosφ
cosφ sinφ- sinφ cosφy
xφ/2
φ/2
y
xφ/2
φ/2
σA·y
σA·xσφ·y
σφ·x
φ/2
φ/2
σA acts1st
σA acts2nd
+φ y
x
−φ
−φ
Symmetry: It’s all done with mirrors!
Fig. 5.3a-e
70Friday, August 28, 2015