Instant Download PDF University Physics With Modern Physics 2nd Edition Bauer Test Bank Full Chapter
Instant Download PDF University Physics With Modern Physics 2nd Edition Bauer Test Bank Full Chapter
Instant Download PDF University Physics With Modern Physics 2nd Edition Bauer Test Bank Full Chapter
https://testbankfan.com/product/university-physics-with-modern-
physics-2nd-edition-bauer-solutions-manual/
https://testbankfan.com/product/university-physics-with-modern-
physics-14th-edition-young-test-bank/
https://testbankfan.com/product/university-physics-with-modern-
physics-4th-edition-young-test-bank/
https://testbankfan.com/product/university-physics-with-modern-
physics-4th-edition-young-solutions-manual/
University Physics with Modern Physics 14th Edition
Young Solutions Manual
https://testbankfan.com/product/university-physics-with-modern-
physics-14th-edition-young-solutions-manual/
https://testbankfan.com/product/university-physics-with-modern-
physics-technology-update-13th-edition-young-test-bank/
https://testbankfan.com/product/university-physics-with-modern-
physics-technology-update-13th-edition-young-solutions-manual/
https://testbankfan.com/product/modern-physics-2nd-edition-
harris-solutions-manual/
https://testbankfan.com/product/college-physics-strategic-
approach-with-mastering-physics-2nd-edition-knight-test-bank/
Chapter 8: Systems of Particles and Extended Objects
r1m1 + r2 m2
R= (0.1)
m1 + m2
x1m1 + x2 m2 y m + y2 m2 zm +z m
X= , Y= 1 1 , Z= 1 1 2 2 (0.2)
m1 + m2 m1 + m2 m1 + m2
r1m1 + r2 m2 + + rn mn år m i i
1 n
R=
m1 + m2 + + mn
= i=1
n
= år m
M i=1 i i
(0.3)
åm i
i=1
n
M = å mi (0.4)
i=1
1 n 1 n 1 n
X= å x m
M i=1 i i
; Y = å y m
M i=1 i i
; Z = åz m
M i=1 i i
(0.5)
d dæ 1 n ö 1 n d 1 n 1 n
V º R = ç å ri mi ÷ = å mi ri = å mi vi = å pi (0.6)
dt dt è M i=1 ø M i=1 dt M i=1 M i=1
n
P = MV = å pi (0.7)
i=1
d d dæ n ö n d n
P = ( MV ) = ç å pi ÷ = å pi = å Fi (0.8)
dt dt dt è i=1 ø i=1 dt i=1
d
P = Fnet (0.9)
dt
pc = vc Dm (0.10)
v1 = v0 + Dv = 0 + Dv = Dv1 (0.11)
vc Dm
Dv1 = - (0.12)
m0 - m
vc Dm
Dvn = - (0.13)
m0 - nDm
- Chapter 8 -
Bauer, Westfall: University Physics
vc Dm Dv v
Dv = - Þ =- c (0.14)
m Dm m
dv v
=- c (0.15)
dm m
m
1 m æm ö
v(m) = -vc ò dm' = -vc ln m m = vc ln ç 0 ÷ (0.16)
m0
m' 0 è mø
æm ö æm ö æmö
vf - vi = vc ln ç 0 ÷ - vc ln ç 0 ÷ = vc ln ç i ÷ (0.17)
è mf ø è mi ø è mf ø
dm
Fthrust = -vc (0.18)
dt
dm
r= (0.19)
dV
M
r= (for constant r ) (0.20)
V
1
M Vò
R= r r(r )dV (0.21)
x = r cos f sin q
y = r sin f sin q (0.22)
z = r cosq
r = x2 + y2 + z 2
æ z ö
q = cos -1 ç ÷ (0.23)
çè x 2 + y 2 + z 2 ÷ø
æ yö
f = tan -1 ç ÷
è xø
x = r^ cos f
y = r^ sin f (0.24)
z=z
- Chapter 8 -
Chapter 8: Systems of Particles and Extended Objects
r^ = x 2 + y 2
æ yö
f = tan -1 ç ÷ (0.25)
è xø
z=z
æ ymax æ xmax
zmax
ö ö
ò
V
f (r )dV = ò ç ò ç ò f (r )dx ÷ dy ÷ dz
ç
zmin è ymin è xmin ø ÷ø
(0.26)
æ ymax æ zmax
xmax
ö ö
ò
V
f (r )dV = ò ç ò ç ò f (r )dz ÷ dy ÷ dx
ç
xmin è ymin è zmin ø ÷ø
(0.27)
dV = r^ dr^ df dz (0.28)
æ fmax æ r^max
zmax
ö ö
ò
V
f (r )dV = ò ç ò ç ò f (r )r^ dr^ ÷ df ÷ dz
ç
zmin è fmin è r^min ø ÷ø
(0.29)
dV = r 2 dr sinq dq df (0.30)
æ fmax æ qmax
rmax
ö ö
ò
V
f (r )dV = ò ç ò ç ò f (r )sin q dq ÷ df ÷ r 2 dr
ç
rmin è fmin è q min ø ÷ø
(0.31)
1 1 1
M Vò ò yr(r )dV ; M Vò
X= xr(r )dV ; Y= Z= z r(r )dV (0.32)
M V
r 1
Mò
R= rdV = ò rdV (for constant r ) (0.33)
V
V V
1 1 1
V Vò V Vò V Vò
X= xdV ; Y= ydV ; Z= zdV (0.34)
1 1
M òA ò ys (r )dA
X= xs (r )dA; Y= (0.35)
M A
M = ò s (r )dA (0.36)
A
- Chapter 8 -
Bauer, Westfall: University Physics
1 1
A òA A òA
X= xdA; Y= ydA (0.37)
A = ò dA (0.38)
A
1
M òL
X= xl (x)dx (0.39)
M = ò l (x)dx (0.40)
L
- Chapter 8 -
Another random document with
no related content on Scribd:
the effects of which the unfortunate victim might easily bleed to
death.
Under the category of fighting-sticks we might also mention the
wooden swords, of which some form or other is known all over the
continent.
In its normal form, the sword is a long and narrow, lanceolate
blade of hard and heavy wood, up to five feet in length. The sides
are convex, and the edges fairly sharp. The surfaces are either
smooth or longitudinally grooved, and in addition decorated with
finely incised patterns of different descriptions. These swords are
much used by the Minning tribe of the Eucla district.
The Cooper Creek tribes make the weapon with a slight curve in it,
like a boomerang, the length being about the same as in the
previous type. Among the Dieri it goes by the name of “marriwirri.”
The Arunndta and Aluridja forms are not made so long, but slightly
wider, and of very heavy mulga wood.
In the northern coastal districts, the type is different in so far as it
tapers towards that end, which is to serve as the handle, and
terminates there in a flat or slightly concave base. The haft is not
infrequently bound round with vegetable fibre, and subsequently
covered with beeswax, to prevent the hands from slipping.
These weapons are all used with two hands for striking and
parrying blows during a duel. When about to “receive” a blow, the
native takes the precaution to keep his elbows close against his
body to avoid the risk of having his arm broken by the ricochet of the
heavy weapon. A favourite mark is the opponent’s hands; and the
fighter has to carefully guard them by adroitly and instantly shifting
the sword sideways the moment he perceives that the blow has
been aimed at them.
The northern and north-western tribes use light reed spears when
settling quarrels between two individuals. The spear is about five feet
long and has a tapering head of mangrove wood, which is inserted
into the top end of the reed shaft. All coastal tribes, from the
Adelaide River westwards to the Ord River, use this spear, but it is
not known in central Australia. The opponents, standing about forty
or fifty feet apart, throw the weapons at each other with wonderful
precision, but before the dangerous little missile can reach its mark,
the would-be recipient dodges it with equal skill. A number of such
spears is carried by each combatant. Whilst the duel is proceeding,
the two natives dance in defiance to taunt the rival, grotesquely
jumping from one foot to the other, holding the arms semi-erect and
bent at the elbows and wrists, whilst the body is thrown forward and
the head kept back. When a spear passes very near to or grazes its
mark, the native greets his escape with a short but strangely
articulated exclamation sounding like “irr.” The throwers are
constantly on the move, and, whenever possible, one stoops to pick
up a new spear from a bundle of them lying at his side. The little
missiles are so light that, when they hit the ground, they skip along
the surface and can be recovered uninjured. Although these spears
seem more like toys than weapons, they are nevertheless most
formidable on account of their sharp point and the velocity with which
they travel.
A method which is in vogue among the central Australian tribes,
like the Arunndta and Dieri, is the dagger duel. The dagger
employed is a long stone-knife with a grip or haft of porcupine resin;
the Arunndta name for it is “putta ildurra.” The combatants hold one
of such daggers in one hand and a light shield of kurrajong wood in
the other, and thus equipped they approach each other. After some
preliminaries in the way of dancing and an accompaniment of
excited shrieking, the men close in upon one another. With the shield
they not only catch the well-directed stabs before any bodily injury is
done, but they also thrust the opponent back to keep him at arm’s
length. It is not an uncommon event for such a duel to be fought for a
considerable time without any bloodshed, the skilful parrying
checking many a fatal blow until eventually utter exhaustion
appeases the thirst for revenge and soothes the hatred, which was
only too evident at the beginning of the duel. At other times severe
gashes are inflicted, which occasionally terminate fatally. Vide Fig. 4.
Fig. 4. Two Arunndta carvings of scenes in a dagger-duel (× 1/3). Tracing.
PLATE XXIII
“One man cowers upon the ground ... whilst the second, kneeling at the side of
him, holds his pointing stick at arm’s length....”
Any fully initiated men may make use of a pointing-bone or stick,
but when the grievance concerns the tribe in general, the operation
is performed by the magician or medicine man. Women do not
generally carry these sticks, but the Aluridja, and no doubt others
also, allow their gins to charm their yam-sticks, with which they then
“kill” their antagonists. A charmed yam-stick is believed to paralyse
the arms of any person, whom it touches, when appealed to by the
owner; consequently one of this kind is chosen for duelling whenever
possible.
When a man has been condemned to death, the person or
persons, who are to administer the fatal charm, are nominated. The
“pointing” apparatus are produced, and with them the men take up a
kneeling position a little distance away from the camp. Facing the
doomed man’s habitation, they lift the bone, or stick, to shoulder
height and point it at the victim. The long piece of hair-string, which
is attached to the instrument, is tightly tied around the charmer’s
arm, above the elbow. This is done to endow his system with the
magic influence of the pointing-stick he is holding; and that magic, he
believes, passes into the destructive words, which he is uttering:
“May your skeleton become saturated with the foulness of my stick,
so that your flesh will rot and its stench attract the grubs, which live
in the ground, to come and devour it. May your bones turn to water
and soak into the sand, so that your spirit may never know your
whereabouts. May the wind shrivel your skin like a leaf before a fire,
and your blood dry up like the mud in a clay-pan.”
There is a great number of different methods employed in
administering the fatal charm of the pointing-stick, all of which,
however, are after much the same principle. A common practice
amongst the Aluridja is for the man, about to use the stick, to leave
the camp and seclude himself behind a tree or other obstacle. He
squats upon the heel of one foot which he has tucked under his
body. He points the bone or stick straight at the man who is to die,
or, it may be, merely in the direction he imagines he would strike
him. Whilst administering the curse, he holds the object in the hand
of his outstretched right arm.
Both the Arunndta and Aluridja often work in pairs after the
following style: One man cowers upon the ground, with or without his
pointing-stick in his hand, whilst the second, kneeling at the side of
him, holds his pointing-stick at arm’s length over the former man’s
back, and directs it towards the person who is about to receive the
evil charm. Vide Plate XXIII.
To make their charm more effective, and the death-penalty more
certain, central Australian tribes not uncommonly tie the claws of a
bird of prey, the eagle-hawk by preference, to the pointing
instrument. It is believed that by this trick the evil magic works like
the grip of a bird, by clutching the doomed one’s chest and crushing
it. If by accident the unfortunate fellow becomes cognizant of this,
and it happens that, as actually is frequently the case after a big
feast, he suffers from indigestion, he naturally interprets the
symptoms of his indisposition as being due to the invisible, tightening
girth, which the charm has laid about him. The fatal termination
arrives at a much earlier date in consequence.
A man who discovers that he is being boned by an enemy is,
indeed, a pitiable sight. He stands aghast, with his eyes staring at
the treacherous pointer, and with his hands lifted as though to ward
off the lethal medium, which he imagines is pouring into his body
(Plate XXIV). His cheeks blanch and his eyes become glassy, and
the expression of his face becomes horribly distorted, like that of one
stricken with palsy. He attempts to shriek, but usually the sound
chokes in his throat, and all one might see is froth at his mouth. His
body begins to tremble and the muscles twitch involuntarily. He
sways backwards and falls to the ground, and for a short time
appears to be in a swoon; but soon after he begins to writhe as if in
mortal agony, and, covering his face with his hands, begin to moan.
After a while he becomes more composed and crawls to his wurley.
From this time onwards he sickens and frets, refusing to eat, and
keeping aloof from the daily affairs of the tribe. Unless help is
forthcoming in the shape of a counter-charm, administered by the
hands of the “Nangarri” or medicine-man, his death is only a matter
of a comparatively short time. If the coming of the medicine-man is
opportune, he might be saved.
The medicine-man of Australian tribes is not so much an individual
who has the knowledge of medicinal values of herbs and of surgical
practices as one who is the recognized sorcerer, capable of rebuking
the ills wrought by an enemy or evil spirit (Plate VIII). He attains his
distinction either by heredity or by accidental, but maybe exemplary,
craftiness. In the former case, he is looked upon as a favoured son,
who has inherited from his tribal and ancestral fathers the magic art
of neutralizing the evil charm of a spirit or enemy, which manifests
itself in prostration or disease; at the same time he is the official
power of the community, who alone can outwit the evil spirit, control
the elements, and keep pestilence away from the camp. This
hereditary art is recognized as a concrete matter, which is believed
to have been deposited within the body of the particular individual by
spirit-ancestors or nearer spirit-relations; this matter might have
taken the form of a special variety of wood, small bones of animal or
man, and a number of sacred stones, all of which the made
medicine-man carries about with him in his abdomen, more or less
replacing the ordinary entrails originally occupying the cavity. Each
tribe has a number of these medicine-men, whose rank is gauged
according to age and the principle they have lived up to. For
instance, in the qualification of the early medicine-men of the
Adelaide tribe, it was deemed necessary that the candidate should
taste human flesh at least once is his life. In the central Australian
tribes a medicine-man should not eat of kangaroo which has been
feeding upon new green grass; if he does, some of his mystic
powers will leak out of his body, and he will immediately drop in the
estimation of his tribal admirers. If the offence is repeated a number
of times, he is disrespected entirely as a professional sorcerer. There
are, of course, a great number of restrictions, which the
conscientious practitioner observes most punctiliously.
Every medicine-man of any standing at all has his own history of
qualification, which he does not hesitate to make known to the public
at opportune moments. Old Kai Kai, the leading Nangarri of the
western Arunndta on the Finke River, relates how he, as a young
hunter, became detached from the rest of the party, and, after
tracking a wounded kangaroo for a whole day, he eventually
abandoned the pursuit to make for a rock-hole in the stony James
Ranges. It was nigh on sunset when he arrived at the hole, tired and
thirsty. He threw his wommera and spears upon the ground, and
eagerly lay over the cool fluid to still his parching thirst. But when he
sipped the water a tadpole entered his mouth, and, before he could
spit it out, it slipped down his gullet and dropped into his abdominal
cavity with a bump that caused him much pain. When he recovered,
he again tried to soothe his burning lips, but met with a similar fate.
Several times more he tried, but in vain; as soon as his burning lips
touched the surface of the water, a slimy tadpole slipped into his
mouth and fell into his stomach with a painful thud. In desperation he
made a final attempt to carefully approach the water’s level, when he
beheld what he took to be the image of his face and body reflected
from below. Horror overcame him, however, for the image was that
of another man! And, as he looked again, he noticed that the body of
the image was transparent, and inside of it there were just as many
rounded pebbles as he had swallowed tadpoles! He collapsed at the
side of the waterhole and slept like a dead man, for how long he
could not say. When at length he woke up, he found himself among
the reeds of the flowing sheet of water on the Finke River, which the
white people call Running Waters. He now quenched his thirst. And
when the recollections of his experience at the rock-hole came back
to him, he realized that the man who had looked at him through the
water had been a spirit, and he could still feel the pebbles he had
placed inside of him. Now it was obvious to him that he had been
ordained a Nangarri, and he returned to his camp, where his
relatives were anxiously awaiting him.
Having been called to the side of a “boned” patient, the Nangarri
allows a number of the relatives to be present when he applies his
weird method of treatment. At first he cuts some ridiculous antics,
during which he mumbles or chants some almost inaudible verses.
The patient is, in the meantime, laid flat on the ground. The Nangarri
approaches the sufferer from the foot end and, throwing himself
upon the ground, crawls right on to the chest of the former, biting the
skin of his patient at several places as he crawls on to the body.
Having “located” the seat of the trouble, the “doctor” slips on to the
ground, and, picking up a fold of the skin with the underlying fatty
tissue between his fingers over the vital spot, applies his lips, and,
perhaps, his teeth, too, to it. He sucks, bites, and kneads the skin,
frequently lifting his head and spitting blood on to the ground. The
patient is all the while groaning with pain; if he becomes
unmanageable, he is called to order by the Nangarri. At length the
climax arrives. The Nangarri withdraws from the patient, his cheeks
visibly inflated, and, conscious of the expectant eyes of all present,
he empties the contents of his mouth into his hands, which he holds
like a receptacle in front of him. The fluid, consisting of saliva and
blood, is allowed to trickle to the ground or into the fire. Then a
triumphant chuckle announces that the malignant element has been
discovered! With feigned exaltation, the great healer steps towards
the awe-stricken relatives, holding between the index-finger and
thumb of his right hand an article, such as a small stick, a bone, a
pebble, a meteoric bomb, or a talon, which he avows is the cause of
the “boned” man’s affliction, and, having now been skillfully and
permanently removed, the unhappy fellow has nothing more to tear.
The good news is immediately conveyed to the prostrate form on
the ground. The effect is astounding. The miserable fellow, until that
moment well on the road to death, raises his head to gaze in
wonderment upon the object held by the Nangarri, which, in all
seriousness, he imagines has been extracted from the inside of his
body. Satisfied with its reality, he even lifts himself into a sitting
position and calls for some water to drink. The crisis has now been
passed, and the patient’s recovery is speedy and complete. Without
the Nangarri’s interception, the “boned” fellow would have fretted
himself to death for a certainty, but the sight of a concrete object,
claimed by the recognized authority of the tribe to be the cause of
the complaint, signifies recovery to him, and with its removal comes
a new lease of life. The implicit faith a native cherishes in the magic
powers of his tribal medicine-man results in cures, which exceed
anything recorded by the faith-healing disciples of more cultured
communities.
CHAPTER XX
WARFARE