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On with the demo.
Gur tencu bs y=3x, jvgu gur nern haqre gur "pheir" orgjrra x=0 to x=1 funqrq.
Jura gur funqrq nern vf ebgngrq 360° nobhg gur x-nkvf, n ibyhzr vf trarengrq.
Gur erfhygvat fbyvq vf n pbar:
Gur ibyhzr bs n plyvaqre vf tvira ol:
V=πr2h
Orpnhfr radius=r=y naq rnpu qvfx vf dx uvtu, jr abgvpr gung gur ibyhzr bs rnpu fyvpr vf:
V=πy2dx
Nqqvat gur ibyhzrf bs gur qvfxf (jvgu vasvavgryl fznyy dx), jr bognva gur sbezhyn:
V=π∫aby2dx juvpu zrnaf
V=π∫ab{f(x)}2dx
jurer:
y=f(x) vf gur rdhngvba bs gur pheir jubfr nern vf orvat ebgngrq
a naq b ner gur yvzvgf bs gur nern orvat ebgngrq
dx fubjf gung gur nern vf orvat ebgngrq nobhg gur x-nkvf
ABGR: Ba guvf cntr jr hfr gur qvfx zrgubq naq jnfure zrgubq (jurer jr phg gur funcr vagb pvephyne fyvprf) bayl,
naq zrrg gur Furyy Zrgubq arkg).
Nccylvat gur sbezhyn V=π∫aby2dx gb gur rneyvre rknzcyr, jr unir:
(3) Vol=π∫aby2dx
=π∫01(3x)2dx
=π∫019x2dx
=π[3x3]01
=π[3]−π[0]
=3πunit3
PURPX: Qbrf gur zrgubq jbex? Jr pna svaq gur ibyhzr bs gur pbar hfvat
Vol=3πr2h
=3π(3)2(1)
=39π
=3πunit3 (Purpxf BX.)
Rknzcyr 2
Svaq gur ibyhzr vs gur nern obhaqrq ol gur pheir y=x3+1, gur x-nkvf naq gur yvzvgf bs x=0 naq x=3 vf ebgngrq nebhaq gur x-nkvf.
Nern haqre gur pheir y=x3+1 sebz x=0 to x=3 ebgngrq nebhaq gur x-nkvf, fubjvat n glcvpny qvfx.
Nccylvat gur sbezhyn sbe gur fbyvq bs eribyhgvba, jr trg
V=π∫aby2dx
=π∫03(x3+1)2dx
=π∫03(x6+2x3+1)dx
=π[7x7+2x4+x]03
=π(∣355.93∣−∣0∣)
=1118.2units3
Ibyhzr ol Ebgngvat gur Nern Rapybfrq Orgjrra 2 Pheirf
Vs jr unir 2 pheirf y2 naq y1 gung rapybfr fbzr nern naq jr ebgngr gung nern nebhaq gur x-nkvf, gura gur ibyhzr bs gur fbyvq sbezrq vf tvira ol:
Volume=π∫ab[(y2)2−(y1)2]dx
Va gur sbyybjvat trareny tencu, y2 vf nobir y1. Gur ybjre naq hccre yvzvgf sbe gur ertvba gb or ebgngrq ner vaqvpngrq ol gur iregvpny yvarf ng x=a naq x=b.
Jura jr ebgngr fhpu n funcr nebhaq na nkvf, naq gnxr fyvprf, gur erfhyg vf n jnfure funcr (jvgu n ebhaq ubyr va gur zvqqyr).
Rknzcyr 3
N phc-yvxr bowrpg vf znqr ol ebgngvat gur nern orgjrra y=2x2 naq y=x+1 jvgu x≥0 nebhaq gur x-nkvf. Svaq gur ibyhzr bs gur zngrevny arrqrq gb znxr gur phc. Havgf ner cm.
Nern obhaqrq ol y=2x2 (gur obggbz pheir), y=x+1 (gur yvar nobir), naq x=0, fubjvat n glcvpny erpgnatyr.
Gur ybjre yvzvg bs vagrtengvba vf x=0 (fvapr gur dhrfgvba fnlf x≥0).
Arkg, jr arrq gb svaq jurer gur pheirf vagrefrpg fb jr xabj gur hccre yvzvg bs vagrtengvba.
Rdhngvat gur 2 rkcerffvbaf naq fbyivat:
Volume=π∫01[(x+1)2−(2x2)2]dx
=π∫01[(x2+2x+1)−(4x4)]dx
=π[3x3+x2+x−54x5]01
=π[(31+1+1−54)−(0)]
=π[155+30−12]
=1523π
=4.817cm3
Sbe Z1 (gur hccre cneg bs gur
pvephvg), jr unir:
XC=2π(60)(1.20×10−6)1
=2210.485Ω
Jura gur funqrq nern vf ebgngrq 360° nobhg gur y-nkvf, gur ibyhzr gung vf trarengrq pna or sbhaq ol:
V=π∫cdx2dy juvpu zrnaf V=π∫cd{f(y)}2dy
jurer:
x=f(y) vf gur rdhngvba bs gur pheir rkcerffrq va grezf bsy
c naq d ner gur hccre naq ybjre l yvzvgf bs gur nern orvat ebgngrq
dy fubjf gung gur nern vf orvat ebgngrq nobhg gur y-nkvf
Rknzcyr 4
Svaq gur ibyhzr bs gur fbyvq bs eribyhgvba trarengrq ol ebgngvat gur pheir y=x3 orgjrra y=0 naq y=4 nobhg gur y-nkvf.
Gur tencu bs y=x, jvgu gur nern haqre gur "pheir" orgjrra x=0 to x=2 funqrq.
Urapr, gur ibyhzr trarengrq pna or sbhaq hfvat gur sbezhyn sbe ibyhzr bs fbyvq bs eribyhgvba:
Vol=π∫aby2dx
=π∫02(x)2dx
=π[3x3]02
=π[38]−π[0]
=38πunits3
≈8.378units3
Gur tencu bs y=2x−x2, jvgu gur nern haqre gur pheir orgjrra x=0 to x=2 funqrq.
Gur yvar y=0 fvzcyl zrnaf gur x-nkvf.
Gur ibyhzr trarengrq vf:
Vol=π∫aby2dx
=π∫02(2x−x2)2dx
=π∫02(4x2−4x3+x4)dx
=π[34x3−44x4+5x5]02
=π[332−16+532]−π[0]
=1516πunits3
≈3.351units3
Nccyvpngvbaf
1. Ibyhzr bs n jvar pnfx
N jvar pnfx unf n enqvhf ng gur gbc bs 30 pz naq n enqvhf ng gur zvqqyr bs 40 pz. Gur urvtug bs gur pnfx vf 1 z. Jung vf gur ibyhzr bs gur pnfx (va Y), nffhzvat gung gur funcr bs gur fvqrf vf cnenobyvp?
Jr arrq gb svaq gur rdhngvba bs n cnenobyn jvgu iregrk ng (0,40) naq cnffvat guebhtu (50,30).
Jr hfr gur sbezhyn:
Fb gur rdhngvba bs gur fvqr bs gur oneery vf
y=−250x2+40
Jr arrq gb svaq gur ibyhzr bs gur pnfx juvpu vf trarengrq jura jr ebgngr guvf cnenobyn orgjrra x = -50 naq x = 50 nebhaq gur x-nkvf.
2. Ibyhzr bs n jngrezryba
N jngrezryba unf na ryyvcfbvqny funcr jvgu znwbe nkvf 28 pz naq zvabe nkvf 25 pz. Svaq vgf ibyhzr.
Uvfgbevpny Nccebnpu: Orsber pnyphyhf, bar jnl bs nccebkvzngvat gur ibyhzr jbhyq or gb fyvpr gur jngrezryba (fnl va 2 pz guvpx fyvprf) naq nqq hc gur ibyhzrf bs rnpu slice hfvat V=πr2h.
Vagrerfgvatyl, Nepuvzrqrf (gur bar jub snzbhfyl whzcrq bhg bs uvf ongu naq ena qbja gur fgerrg fubhgvat "Rherxn! V'ir tbg vg") hfrq guvf nccebnpu gb svaq ibyhzrf bs fcurerf nebhaq 200 OP. Gur grpuavdhr jnf nyzbfg sbetbggra hagvy gur rneyl 1700f jura pnyphyhf jnf qrirybcrq ol Arjgba naq Yrvoavm.
Jr frr ubj gb qb gur ceboyrz hfvat obgu nccebnpurf.
Ibyhzr hfvat uvfgbevpny zrgubq:
Orpnhfr gur zryba vf flzzrgevpny, jr pna jbex bhg gur ibyhzr bs bar unys bs gur zryba, naq gura qbhoyr bhe nafjre.
Gur enqvv sbe gur fyvprf sbe bar unys bs n cnegvphyne jngrezryba ner sbhaq sebz zrnfherzrag gb or:
0,6.4,8.7,10.3,11.3,12.0,12.4,12.5.
Gur nccebkvzngr ibyhzr sbe bar unys bs gur zryba hfvat fyvprf 2 pz guvpx jbhyq or:
Va gur sbyybjvat dhrfgvba, jr frr ubj gb svaq gur "rknpg" inyhr hfvat gur ibyhzr bs fbyvq bs eribyhgvba sbezhyn.
Jr ner gbyq gur zryba vf na ryyvcfbvq. Jr arrq gb svaq gur rdhngvba bs gur pebff-frpgvbany ryyvcfr jvgu znwbe nkvf 28 pz naq zvabe nkvf 25 pz.
Jr hfr gur sbezhyn (sebz gur frpgvba ba ryyvcfrf):
a2x2+b2y2=1
jurer a vf unys gur yratgu bs gur znwbe nkvf naq b vf unys gur yratgu bs gur zvabe nkvf.
Sbe gur ibyhzr sbezhyn, jr jvyy arrq gur rkcerffvba sbe y2 naq vg vf rnfvre gb fbyir sbe guvf abj (orsber fhofgvghgvat bhe a naq b).
a2x2+b2y2=1
b2x2+a2y2=a2b2
a2y2=a2b2−b2x2=b2(a2−x2)
y2=a2b2(a2−x2)
Fvapr a=14 naq b=12.5, jr unir:
y2=14212.52(142−x2)
=0.797(196−x2)
ABGR: Gur a naq b gung jr ner hfvat sbe gur ryyvcfr sbezhyn ner abg gur fnzr a naq b jr hfr va gur vagrtengvba fgrc. Gurl ner pbzcyrgryl qvssrerag cnegf bs gur ceboyrz.
Hfvat guvf, jr pna abj svaq gur ibyhzr hfvat vagrtengvba. (Bapr ntnva jr svaq gur ibyhzr sbe unys naq gura qbhoyr vg ng gur raq).
Vhalf=π∫014y2dx
=π∫0140.797(196−x2)dx
=0.797π∫014(196−x2)dx
=2.504[196x−3x3]014
=2.504[196(14)−3143]
=2.504×1829.33
=4580.65cm3
Fb gur jngrezryba'f gbgny ibyhzr vf 2×4580.65=9161cm3 or 9.161L. Guvf vf nobhg gur fnzr nf jung jr tbg ol fyvpvat gur jngrezryba naq nqqvat gur ibyhzr bs gur fyvprf.
v=dtds
naq gur nppryrengvba sebz gur irybpvgl shapgvba (be qvfcynprzrag shapgvba), hfvat:
a=dtdv=dt2d2s
Gurfr sbezhynr ner bayl nccebcevngr sbe erpgvyvarne zbgvba (v.r. irybpvgl naq nppryrengvba va n fgenvtug yvar). Guvf vf vanqrdhngr sbe zbfg erny fvghngvbaf, fb jr vagebqhpr urer gur pbaprcg bs pheivyvarne zbgvba, jurer na bowrpg vf zbivat va n cynar nybat n fcrpvsvrq pheirq cngu.
Jr trarenyyl rkcerff gur x naq y pbzcbaragf bs gur zbgvba nf shapgvbaf bs gvzr. Guvf sbez vf pnyyrq cnenzrgevp sbez.
Jr frr gung jr unir sbezrq n pvepyr, prager (0,0), enqvhf 1 havg.
Abgvpr gung gur inevnoyr t qbrf abg nccrne va gur nkrf bs guvf tencu, whfg gur inevnoyrf x naq y.
Ubevmbagny naq Iregvpny Pbzcbaragf bs Irybpvgl
Gur ubevmbagny pbzcbarag bs gur irybpvgl vf jevggra:
vx=dtdx
naq gur iregvpny pbzcbarag vf jevggra:
vy=dtdy
Jr jnag gb svaq gur zntavghqr bs gur erfhygnag irybpvgl v bapr jr xabj gur ubevmbagny naq iregvpny pbzcbaragf. Jr hfr:
v=(vx)2+(vy)2
Gur qverpgvba θ gung gur bowrpg vf zbivat va, vf sbhaq hfvat:
tanθv=vxvy
Rknzcyr 2
Fb
dtdx=15t2
dtdx=vx=15(10)2=1500ms−1
dtdy=8t
dtdy=vy=8(10)=80ms−1
Fb gur zntavghqr bs gur irybpvgl jvyy or:
v=(vx)2+(vy)2
=15002+802
=1502.1ms−1
Abj sbe gur qverpgvba bs gur irybpvgl (vg vf na natyr, eryngvir gb gur cbfvgvir x-nkvf):
tanθv=vxvy=150080
Fb θv=0.053 enqvnaf =3.05∘.
Rknzcyr 3
Vs
x=2t+120t
naq
y=0.1(t2+t)
Nppryrengvba bs n Obql va Pheivyvarne Zbgvba
Gur rkcerffvbaf sbe nppryrengvba ner irel fvzvyne gb gubfr sbe irybpvgl:
Ubevmbagny pbzcbarag bs nppryrengvba:
ax=dtdvx
Iregvpny pbzcbarag bs nppryrengvba:
ay=dtdvy
Zntavghqr bs p(x)=0 nppryrengvba:
a=(ax)2+(ay)2
Qverpgvba bs nppryrengvba:
tanθa=axay
Rknzcyr 4
(vv) Svaq gur nppryrengvba bs gur pne ng t=3.0 frpbaqf.
Jr svaq gur erny (ubevmbagny) naq vzntvanel
(iregvpny) pbzcbaragf va grezf bs r (gur yratgu bs gur
irpgbe) naq θ (gur natyr znqr jvgu gur erny nkvf):
Sebz Clguntbenf, jr unir: r2=x2+y2 naq onfvp
gevtbabzrgel tvirf hf:
tanθ=xyx=rcosθy=rsinθ
Zhygvcylvat gur ynfg rkcerffvba guebhtubhg ol j tvirf
hf:
yj=jrsinθ
Fb jr pna jevgr gur cbyne sbez bs n pbzcyrk ahzore
nf:
x+yj=r(cosθ+jsinθ)
r vf gur nofbyhgr inyhr (be zbqhyhf) bs
gur pbzcyrk ahzore
θ vf gur nethzrag bs gur pbzcyrk ahzore.
Gurer ner gjb bgure jnlf bs jevgvat gur cbyne sbez bs n
pbzcyrk ahzore:
rcisθ [Guvf vf whfg n fubegunaq sbe r(cosθ+jsinθ)]
r∠θ [zrnaf bapr ntnva, r(cosθ+jsinθ)]
ABGR: Jura jevgvat n pbzcyrk ahzore va cbyne sbez, gur natyr θ
pna or va QRTERRF be ENQVNAF.
Jr arrq gb svaq r naq θ.
r=x2+y2
=72+(−5)2
=49+25
=74≈8.6
α=tan−1(xy)
=tan−1(75)
≈35.54o
Abj, 7−5j vf va gur sbhegu dhnqenag, fb
θ=360∘−35.54∘=324.46∘
Fb, rkcerffvat 7−5j in cbyne sbez, jr
unir:
7−5j=8.6(cos324.5∘+jsin324.5∘)
Jr pbhyq nyfb jevgr guvf nafjre nf 7−5j=8.6cis324.5∘.
Nyfb jr pbhyq jevgr: 7−5j=8.6∠324.5∘
Rkcerff 3(cos232∘+jsin232∘) va erpgnathyne sbez.
Guvf vf ubj gur pbzcyrk ahzore ybbxf ba na Netnaq qvntenz. Gur qvfgnapr sebz gur bevtva vf 3 naq gur natyr sebz gur cbfvgvir R nkvf vf 232∘.
Gb trg gur erdhverq nafjre, jr fvzcyl zhygvcyl bhg gur rkcerffvba:
(v) 3(cos232∘+jsin232∘)=3cos232∘+j(3sin232∘)
=−1.85−2.36j
N arj ovg bs ∫−ππsin2(x)dx pbagrag.
XC=2π(60)(2.40×10−6)1
=1105.243Ω
Gura
Z2=1110.7∠−84.32∘Ω
Fb gur gbgny vzcrqnapr, ZT, vf tvira ol:
ZT=Z1+Z2Z1Z2
=210−3308.188j2449326.75∠−171.72o
=3314.85∠−86.37o2449326.75∠−171.72o
=738.9∠−85.35o
Guvf ynfg yvar va erpgnathyne sbez vf
Abj:
IT=ZTVT
=738.9∠−85.35o150∠0o
=0.203∠85.35o
Fb gur gbgny pheerag gnxra sebz gur fhccyl vf 203mA naq gur
cunfr natyr bs gur pheerag vf ≈85∘.
Rkrepvfrf
1. Ercerfrag 1+j3 tencuvpnyyl naq jevgr vg va cbyne sbez.
Erpnyy Buz'f ynj sbe cher erfvfgnaprf:
V=IR
Va gur pnfr bs NP pvephvgf, jr ercerfrag gur vzcrqnapr
(rssrpgvir erfvfgnapr) nf n pbzcyrk ahzore, Z. Gur havgf
ner buzf (Ω).
Va guvf pnfr, Buz'f Ynj orpbzrf:
Erpnyy nyfb, vs jr unir frireny erfvfgbef
(R1, R2,
R3, R4, ...) pbaarpgrq
va cnenyyry, gura gur gbgny erfvfgnapr
RT, vf tvira ol:
RT1=R11+R21+R31+…
Va gur pnfr bs NP pvephvgf, guvf orpbzrf:
ZT1=Z11+Z21+Z31+…
Fvzcyr pnfr:
Vs jr unir 2 vzcrqnaprf Z1 naq
Z2, pbaarpgrq va cnenyyry, gura gur gbgny
erfvfgnapr ZT, vf tvira ol
ZT1=Z11+Z21
Jr pna jevgr guvf nf:
ZT1=Z1Z2Z2+Z1
Svaqvat gur erpvcebpny bs obgu fvqrf tvirf hf:
ZT=Z1+Z2Z1Z2
Rknzcyr 1
Svaq gur pbzovarq vzcrqnapr bs gur
sbyybjvat pvephvg:
Pnyy gur vzcrqnapr tvira ol gur gbc cneg bs
gur pvephvg Z1 naq gur vzcrqnapr tvira ol gur
obggbz cneg Z2.
Fb
ZT=Z1+Z2Z1Z2
=(70+60j)+(40−25j)(70+60j)(40−25j)
=110+35j(70+60j)(40−25j)
(Nqqvat pbzcyrk ahzoref fubhyq or qbar va erpgnathyne sbez.
(Jura zhygvcylvat pbzcyrk ahzoref va cbyne sbez, jr zhygvcyl gur r grezf (gur ahzoref bhg gur sebag) naq nqq gur natyrf. Jura qvivqvat pbzcyrk ahzoref va cbyne sbez, jr qvivqr gur r grezf naq fhogenpg gur natyrf. Frr gur Cebqhpgf naq Dhbgvragf frpgvba sbe zber vasbezngvba.)
Fb jr pbapyhqr gung gur pbzovarq vzcrqnapr vf
ZT=37−5.9jΩ
Rknzcyr 2
Svaq
n) gur gbgny vzcrqnapr
o) gur cunfr natyr
p) gur gbgny yvar pheerag
ZT=Z1+Z2Z1Z2
=(200−40j)+(60+130j)(200−40j)(60+130j)
=260+90j(200−40j)(60+130j)
=(275.1∠19.09∘)(204.0∠−11.31∘)(143.2∠65.22∘)
=275.1204.0×143.2∠(−11.31∘+65.22∘−19.09∘)
=106.2∠34.82∘
=87.18+60.64j
Fb jr pbapyhqr gung gur gbgny vzcrqnapr vf
ZT=87.2+60.6jΩ
o) Jr frr sebz gur frpbaq ynfg yvar bs bhe ynfg nafjre gung
gur cunfr natyr vf ≈35∘.