physics

Kev daws teeb meem hauv kev txav mus los ncaj qha - cov khoom poob dawb

1. Ib yam khoom poob los ntawm saum ib lub pob tsuas. Pom tias nws ntaus hauv av tom qab 3 vib nas this. Txheeb xyuas nws qhov ceev ua ntej ntaus hauv av. Kev nrawm ntawm lub ntiajteb txawj nqus yog 10 m/s²Tsis quav ntsej txog kev tiv thaiv cua.

Paub:

Qhov ceev pib (v_o) = 0 (khoom poob lawm)

Lub sijhawm luv (t) = 3 vib nas this

Kev nrawm ntawm lub ntiajteb txawj nqus (g) = 10 m/s²

Xav tau: Qhov ceev kawg (v_t)

Tshuaj:

Kev nrawm vim yog lub ntiajteb txawj nqus ntawm qhov chaw ntawm lub ntiaj teb, nws qhov loj yog 9.8 m / s²Yuav kom ua kom yooj yim dua rau kev xam lej, peb siv 10 m/s².

10 m / s² los yog 10 m/s / 1 vib nas this, txhais tau tias qhov ceev nce linearly hauv lub sijhawm los ntawm 10 m/s thaum txhua vib nas this.

Tom qab 1 vib nas this, qhov ceev ntawm yam khoom = 10 m/s

Tom qab 2 vib nas this, qhov ceev ntawm yam khoom = 20 m/s

Tom qab 3 vib nas this, qhov ceev ntawm yam khoom = 30 m/s.

Peb kuj tseem siv tau cov kinematic equations rau kev txav mus los ntawm kev nrawm tas li, raws li qhia hauv qab no.

v_t = v_o + ntawm

s = v_o t + ½ ntawm²

v_t² = v_o² + 2 lub qag

Kev poob dawb tsis muaj qhov ceev pib (v)_o = 0), yog li ntawd, cov kab zauv saum toj no tuaj yeem hloov pauv raws li qhia hauv qab no:

Kev sib npaug ntawm Kev txav mus los ntawm kev poob dawb :

v_t = gt ………… 1

h = ½ gt² ………… 2

v_t² = 2 gh ………….. 3

v_t = gt

v_t = (10)(3)

v_t = 30 m/s

Qhov ceev kawg yog 30 m/s

2. Ib lub cev poob dawb paug los ntawm qhov chaw so, ntawm qhov siab ntawm 25 m. Nrhiav (a) Qhov ceev uas nws ntaus hauv av. (b) Lub sijhawm uas nws siv los mus txog hauv av.

Kev nrawm vim yog lub ntiajteb txawj nqus ntawm qhov chaw ntawm lub ntiaj teb yog 10 m / s².

Paub:

Qhov siab (h) = 5 meters

Kev nrawm ntawm lub ntiajteb txawj nqus (g) = 10 m/s²

Xav tau:

(a) Qhov ceev kawg (v_t)

(b) Lub sijhawm luv (t)

Tshuaj:

Kev sib npaug ntawm kev poob dawb:

v_t = gt

h = ½ gt²

v_t² = 2 gh

(a) Qhov ceev kawg (v_t)

v_t² = 2 gh = 2(10)(5) = 100

v_t = 10 m/s

(b) Lub sijhawm luv (t)

h = ½ gt²

5 = ½ (10) t²

5 = 5 t²

t² = 5/5 = 1

t = 1 vib nas this

3. Ib lub pob poob ntawm qhov siab. Nrhiav (a) Kev nrawm (b) Qhov deb tom qab 3 vib nas this (c) Lub sijhawm nyob hauv huab cua yog tias qhov ceev kawg yog 20 m/s. Kev nrawm vim lub ntiajteb txawj nqus = 10 m/s²

Paub Tias :

Kev nrawm ntawm lub ntiajteb txawj nqus (g) = 10 m/s²

Xav tau:

(a) Kev nrawm (a)

(B) Ze los yog qhov siab (h) yog tias lub sijhawm dhau mus (t) = 3 vib nas this

(c) Lub sijhawm luv (t) yog tias v_t = 20 m/s

Tshuaj:

Kev sib npaug ntawm kev poob dawb:

v_t = gt

h = ½ gt²

v_t² = 2 gh

(a) Kev nrawm (a)

Kev nrawm = kev nrawm vim lub ntiajteb txawj nqus = 10 m/s²Nws txhais tau tias qhov ceev nce ntxiv 10 m/s ib ob.

(b) Qhov deb lossis qhov siab (h) tom qab t = 3 vib nas this

h = ½ gt² = ½ (10)(3)² = (5)(9) = 45 meters

(c) Lub sijhawm dhau mus (t) yog tias v_t = 20 m/s

v_t = gt

20 = (10) t

t = 20 / 10 = 2 vib nas this

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1. Qhov nrug thiab kev hloov chaw
2. Qhov nruab nrab ntawm qhov ceev thiab qhov nruab nrab ntawm qhov ceev
3. Qhov ceev tas mus li
4. Tsis tu ncua acceleration
5. Kev txav mus los ntawm kev poob dawb
6. Kev txav mus los hauv lub caij nplooj zeeg dawb
7. Kev txav mus rau saum thiab nqis hauv lub caij nplooj zeeg dawb

nyeem ntxiv

Tau daws cov teeb meem hauv kev txav mus los ncaj - kev nrawm tas li

1. Ib lub tsheb khiav nrawm ntawm qhov chaw so mus txog 20 m/s hauv 10 vib nas this. Txheeb xyuas qhov nrawm ntawm lub tsheb!

tshuaj

Paub:

Qhov ceev pib (v_o) = 0 (so)

Lub sijhawm luv (t) = 10 vib nas this

Qhov ceev kawg (v_t) = 20 m/s

xav : Kev nrawm (a)

Tshuaj:

v_t = v_o + ntawm

20 = 0 + (a)(10)

20 = 10 ib

ib = 20 / 10

ib = 2 m/s²

2. Lub tsheb qeeb qeeb ntawm 30 m/s mus so hauv 10 vib nas this. Txheeb xyuas qhov kev nrawm ntawm lub tsheb.

tshuaj

Paub:

Qhov ceev pib (v_o) = 30 m/s

Qhov ceev kawg (v_t= 0 TZS

Lub sijhawm luv (t) = 10 vib nas this

Xav tau: kev ua kom nrawm (a)

Tshuaj:

v_t = v_o + ntawm

0 = 30 + (a)(10)

– 30 = 10 ib

ib = – 30 / 10

ib = -3 m/s²

Lub cim tsis zoo tshwm sim vim tias qhov kawg tshaj tawm tsawg dua qhov ceev pib.

3. Lub tsheb pib thiab nrawm nrawm nrog qhov ceev tas li 4 m/s² in 1 vib nas this. Txheeb xyuas ceev thiab qhov deb tom qab 10 vib nas this.

tshuaj

(a) Ceev

Kev nrawm 4 m/s² txhais tau tias qhov ceev nce 4 m/s txhua 1 vib nas this. Tom qab 2 vib nas this, lub tsheb qhov ceev yog 8 m/s. Tom qab 10 vib nas this, lub tsheb qhov ceev yog 40 m/s.

(b) Qhov Deb

Paub:

Qhov ceev pib (v_o= 0 TZS

Qhov ceev kawg (v_t) = 40 m/s

Kev nrawm (a) = 4 m/s²

Xav tau: Ze

Tshuaj:

s = v_o t + ½ ntawm² = 0 + ½ (4)(10)²) = (2)(100) = 200 meters

4. Lub tsheb khiav ceev tas li 10 m/s, ces qeeb qeeb li 2 m/s² kom txog thaum so. Txheeb xyuas lub sijhawm dhau los thiab lub tsheb deb ua ntej so.

Paub:

Qhov ceev pib (v_o) = 10 m/s

Kev nrawm (a) = -2 m/s² (Lub cim tsis zoo tshwm sim vim tias qhov ceev kawg tsawg dua qhov ceev pib)

Qhov ceev kawg (v_t) = 0 (so)

Xav tau: Lub sijhawm thiab qhov deb

Tshuaj:

(a) Lub sijhawm luv (t)

v_t = v_o + ntawm

0 = 10 + (-2)(t)

0 = 10 – 2 t

10 = 2 t

t = 10 / 2 = 5 vib nas this

(b) Qhov Deb

v_t² = v_o² + 2 lub qag

0 = 10² + 2(-2) vib nas this

0 = 100 – 4 vib nas this

100 = 4 vib nas this

s = 100 / 4 = 25 meters

5. Lub tsheb khiav ceev 40 m/s, qeeb qeeb li 4 m/s tas li² kom txog thaum so. Txheeb xyuas qhov ceev thiab qhov deb tom qab qeeb qeeb hauv 10 vib nas this!

tshuaj

Paub:

Qhov ceev pib (v_o) = 40 m/s

Kev nrawm (a) = -4 m/s²

Lub sijhawm luv (t) = 10 vib nas this

Xav tau: qhov ceev kawg (v_t) thiab qhov deb (s)

Tshuaj:

(a) Qhov ceev kawg

v_t = v_o + ntawm = 40 + (-4)(10) = 40 – 40 = 0 m/s

0 m/s txhais tau tias lub tsheb so.

(b) Qhov Deb

s = v_o t + ½ ntawm² = (40)(10) + ½ (-4)(10)²) = 400 + (-2)(100) = 400 – 200 = 200 meters

6. Txheeb xyuas qhov deb tom qab 10 vib nas this!

tshuaj

Sab nrauv: s = vt = (10-0)(5-0) = (10)(5) = 50 meters

7. Txheeb xyuas qhov deb tom qab 4 vib nas this!

tshuaj

Qhov nrug = thaj tsam plaub fab + thaj tsam peb ceg

Qhov Nrug = (8-0)(8-0) + ½ (16-8)(8-0) = (8)(8) + ½ (8)(8) = 64 + 32 = 96 meters

8. Txheeb xyuas qhov deb ntawm lub tsheb tom qab 4 vib nas this!

tshuaj

Qhov Nrug Deb = Thaj chaw peb ceg = ½ (4-0)(8-0) = ½ (4)(8) = 16 meters

9. Muaj ib lub tsheb khiav ceev li ntawm 90 km/h dhau ib lub tsheb tub ceev xwm uas nres ntawm ntug kev. Ib feeb tom qab, lub tsheb tub ceev xwm caum at 0.8 m / s²Lub tsheb tub ceev xwm mus txog deb npaum li cases lub tsheb?

Paub:

Qhov ceev ntawm lub tsheb (v) = 90 km/teev = 90,000 meters / 3600 vib nas this = 25 meters/ vib nas this

Lub sijhawm sib nrug (t) = 1 feeb = 60 vib nas this

Kev nrawm ntawm tub ceev xwm lub tsheb (a) = 0.8 m/s²

Qhov ceev pib ntawm tub ceev xwm lub tsheb (v)_o) = 0 m/s

Xav tau: Qhov deb uas lub tsheb tub ceev xwm tau mus

Tshuaj:

Lub tsheb txav mus rau qhov ceev tas li. Qhov deb uas lub tsheb tau mus:

Qhov deb pib:

s = vt = (25)(60) = 1500 meters

Qhov deb kawg:

s = vt = (25)(t)

Tag nrho qhov deb = 1500 + 25 t

Tub ceev xwm lub tsheb txav mus los nrog kev nrawm tas li. Qhov deb uas tub ceev xwm lub tsheb taug kev:

s = v_o t + ½ ntawm² = (0)(t) + ½ (0.8)(t)²) = 0 + 0.4 t² = 0.4 t²

Thaum lub tsheb tub ceev xwm mus txog lub tsheb, qhov deb uas tub ceev xwm lub tsheb mus tau yog tib yam li qhov deb uas lub tsheb mus tau.

Qhov deb ntawm lub tsheb mus ncig = qhov deb uas tub ceev xwm lub tsheb taug kev

1500 + 25 t = 0.4 t²

0.4 t² – 25 t – 1500 = 0

Siv cov qauv quadratic:

Qhov deb uas lub tsheb tub ceev xwm tau mus:

s = 0.4 t² = (0.4)(100²) = (0.4)(10,000) = 4000 meterss = 4 km

10. A tsheb txav mus rau qhov tsis tu ncua 24 m / s brakes kom nws muaj ib qho kev qeeb qeeb tas li ntawm 0.952 m/s². Txheeb xyuas qhov ceev ntawm lub tsheb atom qab qhov deb ntawm 250 meters.

Paub:

Qhov ceev pib (v_o) = 24 m/s

acceleration (a) = – 0.952 m/s² (kos npe tsis zoo vim yog kev qeeb qeeb)

Ze (d) = 250 'meter's

Xav tau: Qhov ceev ntawm lub tsheb tom qab 250 'meter's

Tshuaj:

Paub: qhov ceev pib (v_o), acceleration (ib tug), deb (d), xav tau: qhov ceev kawg (v_t) yog li ntawd siv qhov sib npaug ntawm v_t² = v_o² + 2 ib d

v_t = qhov ceev kawgnyob rau hauv_o = qhov ceev pib, ib = acceleration, d = deb

v_t² = (24)² + (2)(-0.952)(250)

v_t² = 576-476

v_t² = 100

v_t = √100

v_t = 10 m/s

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1. Qhov nrug thiab kev hloov chaw
2. Qhov nruab nrab ntawm qhov ceev thiab qhov nruab nrab ntawm qhov ceev
3. Qhov ceev tas mus li
4. Tsis tu ncua acceleration
5. Kev txav mus los ntawm kev poob dawb
6. Kev txav mus los hauv lub caij nplooj zeeg dawb
7. Kev txav mus rau saum thiab nqis hauv lub caij nplooj zeeg dawb

nyeem ntxiv

Tau daws cov teeb meem hauv kev txav mus los ncaj - Qhov ceev tas mus li

1. Ib lub tsheb khiav nrog qhov ceev tas li 10 m/s. Txheeb xyuas seb deb tom qab 10 vib nas this thiab 60 vib nas this.

tshuaj

Qhov ceev tas li 10 meters/ob txhais tau tias lub tsheb mus ncig 10 meters txhua 1 ob.

Tom qab 2 vib nas this, lub tsheb mus txog 20 meters,

Tom qab 5 vib nas this, lub tsheb mus txog 50 meters,

Tom qab 10 vib nas this, lub tsheb mus txog 100 meters,

Tom qab 60 vib nas this, lub tsheb mus txog 600 meters.

2. Ib lub tsheb khiav raws txoj kev ncaj nraim nrog qhov ceev tas li 72 km/h. Txheeb xyuas qhov deb ntawm lub tsheb tom qab 2 feeb thiab 5 feeb.

tshuaj

72 km/teev = (72)(1000 meters) / 3600 vib nas this = 72,000 / 3600 vib nas this = 20 meters/thib ob.

Qhov ceev tas li ntawm 20 meters/ob txhais tau tias lub tsheb mus ncig 20 meters txhua 1 ob.

Tom qab 120 vib nas this los yog 2 feeb, lub tsheb mus ncig 20 meters x 120 = 2400 meters,

Tom qab 300 vib nas this los yog 5 feeb, lub tsheb mus ncig 20 meters x 300 = 6000 meters.

3. Ib lub cev taug kev raws txoj kev ncaj nraim li 100 meters hauv 50 vib nas this. Txheeb xyuas qhov ceev ntawm lub cev.

tshuaj

100 meters / 50 vib nas this = 10 meters / 5 vib nas this = 2 meters/ib vib nas this.

4. Txheeb xyuas qhov ceev raws li daim duab hauv qab no….

tshuaj

Ceev = Qhov Deb / lub sijhawm dhau mus

Ceev = 2 meters / 1 vib nas this = 4 meters / 2 vib nas this = 6 meters / 3 vib nas this = 8 meters / 4 vib nas this = 2 meters / vib nas this.

5. Lub tsheb A thiab B sib tsoo ntawm txoj kev sib luag. Thaum qhov deb ntawm ob lub tsheb yog 100 meters, lub tsheb A txav mus nrog qhov ceev tas li ntawm 10 m/s, lub tsheb B txav mus nrog qhov ceev tas li ntawm 40 m/s. Txheeb xyuas (a) qhov deb ntawm lub tsheb A ua ntej dhau lub tsheb B (b) lub sijhawm ua ntej lub tsheb B dhau lub tsheb A.

tshuaj

Lub Tsheb A txav mus nrog qhov ceev tas li ntawm 10 meters/ob vib nas this, txhais tau tias lub tsheb A txav mus txog 10 meters txhua 1 vib nas this. Tom qab 2 vib nas this, lub tsheb A txav mus txog 20 meters.

Lub tsheb B txav mus nrog qhov ceev tas li ntawm 40 meters/ob vib nas this, txhais tau tias lub tsheb B txav mus txog 40 meters txhua 1 vib nas this. Tom qab 2 vib nas this, lub tsheb B txav mus txog 80 meters.

20 meters + 80 meters = 100 meters.

(a) Lub tsheb A deb ua ntej dhau lub tsheb B yog 20 meters. Lub tsheb B deb ua ntej dhau lub tsheb A yog 80 meters.

(b) Lub sijhawm ntawm lub tsheb B ua ntej dhau lub tsheb A yog 2 vib nas this. Lub sijhawm ntawm lub tsheb A ua ntej dhau lub tsheb B yog 2 vib nas this

5. Yog tias lub speedometer ntawm lub tsheb qhia tau tias 108 km/teev, txiav txim siab qhov kev ncua deb uas lub tsheb tau mus hauv ib feeb.

Tshuaj:

Lub ntsuas ceev yog ib lub cuab yeej siv los ntsuas qhov ceev. Qhov ceev ntawm lub tsheb yog 108 km/teev.
108 km/teev = (108) (1000 meters) / 3600 vib nas this = 30 meters/feeb.

1 feeb = 60 vib nas this

Qhov ceev ntawm lub tsheb 30 meters/ib pliag txhais tau tias lub tsheb txav mus txog 30 meters hauv 1 vib nas this.

Tom qab 1 vib nas this, lub tsheb txav mus deb li 1 x 30 meters = 30 meters.

Tom qab 2 vib nas this, lub tsheb txav mus deb li 2 x 30 meters = 60 meters.

Tom qab 60 vib nas this, lub tsheb txav mus deb li 60 x 30 meters = 1800 meters.

6. Tom pov a pob ncaj rau Andrew. Tom thiab Andrew yog sib cais mus txog 10.08 metersLub pob raug pov tseg tav toj thiab txav mus los at 20 m/s (tsis quav ntsej txog lub ntiajteb txawj nqus). Andrew ntauss lub pob 4.00 x 10^-3 vib nas this tom qab lub pob raug pov tseg. Yog tias lub tus neeg ntaus txav mus rau qhov tsis tu ncua ceev ntawm 5.00 m/s, lub pob raug ntaus los ntawm tus neeg ntaus tom qab tus neeg uas ntaus ntawv mus deb heev…

Paub:

Qhov deb ntawm Tom thiab Andrew = 10.08 meters

Qhov ceev ntawm lub pob (v) = 20 m/s

Lub sijhawm luv (t) = 4 x 10^-3 vib nas this = 0.004 vib nas this

Qhov ceev ntawm tus neeg ntaus (v) = 5 m / s

SE pob: Lub pob raug ntaus los ntawm tus neeg ntaus tom qab lub pob txav mus deb li ...

Tshuaj:

Qhov deb ntawm pob:

s₁ = vt = (20)(0.004) = 0.08 meters

Qhov deb ntawm tus neeg ntaus:

s₂ = vt = 5 t

Qhov deb ntawm pob + qhov deb ntawm tus neeg ntaus = qhov deb ntawm Tom thiab Andrew.

0.08 + 5 t = 10.08

5 t = 10.08 – 0.08

5 t = 10

t = 10/5

t = 2 vib nas this

Qhov deb ntawm tus neeg ntaus:

s₂ = vt = 5 t = (5) (2) = 10 meters

7. Ib tug neeg yos hav zoov nrog nws lub tsheb tab tom caum ib tug mos lwj. Lub tsheb khiav ntawm 72 km/h thiab tus mos lwj khiav ntawm qhov ceev ntawm 64.8 km/h. Thaum qhov deb ntawm lub tsheb thiab tus mos lwj yog 2012 meters, tus neeg yos hav zoov tua nws rab phom tua phom. Cov mos txwv tawm ntawm rab phom ntawm 200 m/s. Txheeb xyuas lub sijhawm uas tus mos lwj raug tua.

A. 0.5 vib nas this

B. 1 s

C. 1.25 vib nas this

D. 1.5 vib nas this

Paub:

Qhov ceev ntawm lub tsheb (v_b) = 72 km/h = (72) (1000 m) / 3600 s = 20 m/s

Kev ceev ntawm cov mos lwj (v_r) = 64.8 km / h = (64.8) (1000 m) / 3600 s = 64800 m / 3600 s = 18 m / s

Thaum lub mos txwv raug tua, qhov deb ntawm lub tsheb thiab tus mos lwj (s) = 202 meters

Qhov ceev ntawm hluav taws (v_p) = 20 m/s + 200 m/s = 220 m/s

Cov riam phom uas cov neeg yos hav zoov tuav uas nyob hauv lub tsheb uas txav mus nrog qhov ceev ntawm 20 m/s kom qhov ceev ntawm lub tsheb kuj ntxiv rau qhov ceev ntawm lub mos txwv.

SE pob: Txheeb xyuas lub sijhawm uas cov mos lwj raug tua

Tshuaj:

Xav txog cov tsheb thiab cov mos lwj uas txav mus los ntawm qhov ceev tas li.

Kab zauv: v = s / t los yog s = vt

v = qhov ceev, s = qhov deb, t = lub sijhawm luv

Qhov Nrug Deb = 202 + X_r = 202 + v_r t = 202 + 18 t

Qhov Nrug Deb = Y_p = v_p t = 220 t

Qhov deb uas cov mos lwj taug kev = qhov deb uas cov mos txwv taug kev

202 + 18 t = 220 t

202 = 220 t – 18 t

202 = 202 t

t = 202/202

t = 1 vib nas this

Cov lus teb yog B.

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1. Qhov nrug thiab kev hloov chaw
2. Qhov nruab nrab ntawm qhov ceev thiab qhov nruab nrab ntawm qhov ceev
3. Qhov ceev tas mus li
4. Tsis tu ncua acceleration
5. Kev txav mus los ntawm kev poob dawb
6. Kev txav mus los hauv lub caij nplooj zeeg dawb
7. Kev txav mus rau saum thiab nqis hauv lub caij nplooj zeeg dawb

nyeem ntxiv

Tau daws cov teeb meem hauv kev txav mus los ncaj - Qhov nruab nrab ntawm qhov ceev thiab qhov nruab nrab ntawm qhov ceev

1. Ib lub tsheb khiav raws txoj kev ncaj mus rau sab hnub tuaj li 100 meters hauv 4 vib nas this, ces mus rau sab hnub poob li 50 meters hauv 1 vib nas this. Txheeb xyuas qhov ceev nruab nrab thiab qhov ceev nruab nrab.

tshuaj

Qhov Nrug = 100 meters + 50 meters = 150 meters

xaav = 100 meters – 50 meters = 50 meters, mus rau sab hnub tuaj.

Lub sijhawm dhau mus = 4 vib nas this + 1 vib nas this = 5 vib nas this.

Qhov nruab nrab ntawm qhov ceev = Qhov deb / lub sijhawm dhau mus = 150 meters / 5 vib nas this = 30 meters/ib vib nas this.

Qhov nruab nrab ntawm qhov ceev = Kev Hloov Chaw / lub sijhawm dhau mus = 50 meters / 5 vib nas this = 10 meters/ib vib nas this.

2. Ib tug neeg taug kev 4 meters mus rau sab hnub tuaj hauv 1 vib nas this, tom qab ntawd taug kev 3 meters mus rau sab qaum teb hauv 1 vib nas this. Txheeb xyuas qhov ceev nruab nrab thiab qhov ceev nruab nrab.

tshuaj

Qhov Nrug = 4 meters + 3 meters = 7 meters

Kev Hloov Chaw = = meters, mus rau sab qaum teb sab hnub tuaj.

Lub sijhawm dhau mus = 1 vib nas this + 1 vib nas this = 2 vib nas this.

Qhov nruab nrab ceev = qhov deb / lub sijhawm dhau mus = 7 meters / 2 vib nas this = 3.5 meters / vib nas this

Qhov nruab nrab ntawm qhov ceev = kev hloov chaw / lub sijhawm dhau mus = 5 meters / 2 vib nas this = 2.5 meters/ib pliag

3. Ib tug neeg khiav ncig tebchaws Txoj kev khiav plaub fab uas ntev = 50 meters thiab dav = 20 meters. Tom qab khiav ncig txoj kev khiav plaub fab ob zaug, tus neeg khiav rov qab mus rau qhov chaw pib. Yog tias lub sijhawm dhau mus = 100 vib nas this, txiav txim siab qhov nruab nrab ntawm qhov ceev thiab qhov nruab nrab ntawm qhov ceev.

tshuaj

Lub voj voog ntawm lub duab plaub fab = 2(50 meters) + 2(20 meters) = 100 meters + 40 meters = 140 meters.

Mus ncig lub duab plaub fab 2 zaug = 2(140 meters) = 280 meters.

Qhov Nrug = 280 meters.

Kev Hloov Chaw = 0 meters. (khiav rov qab mus rau qhov chaw pib)

Qhov nruab nrab ntawm qhov ceev = qhov deb / lub sijhawm dhau mus = 280 meters / 100 vib nas this = 2.8 meters / vib nas this.

Qhov nruab nrab ntawm qhov ceev = kev hloov chaw / lub sijhawm dhau mus = 0 / 100 vib nas this = 0.

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1. Qhov nrug thiab kev hloov chaw
2. Qhov nruab nrab ntawm qhov ceev thiab qhov nruab nrab ntawm qhov ceev
3. Qhov ceev tas mus li
4. Tsis tu ncua acceleration
5. Kev txav mus los ntawm kev poob dawb
6. Kev txav mus los hauv lub caij nplooj zeeg dawb
7. Kev txav mus rau saum thiab nqis hauv lub caij nplooj zeeg dawb

nyeem ntxiv

Tau daws cov teeb meem hauv vectors - qhov tshwm sim ntawm ob lub vectors siv cov khoom ntawm lub vector

1. F₁ = 6 N, F₂ = 10 N. Txheeb xyuas qhov vector uas tau txais.

tshuaj

F_1x =F₁ coj 60^o = (6)(0.5) = 3 N (zoo vim nws muaj tib qho kev taw qhia li x axis)

F_2x =F₂ coj 30^o = (10)(0.5√3) = 5√3 = (5)(1.372) = -8.66 N (tsis zoo vim nws muaj tib qho kev taw qhia li -x axis)

F_1y =F₁ kev txhaum 60^o = (6)(0.5√3) = 3√3 = (3)(1.372) = 4.116 N (zoo vim nws muaj tib qho kev taw qhia li y axis)

F_2y =F₂ kev txhaum 30^o = (10)(0.5) = -5 N (tsis zoo vim nws muaj tib qho kev taw qhia li -y axis)

F_x =F_1x - F_2x = 3 – 8.66 = -5.66 N

F_y =F_1y - F_2y = 4.116 – 5 = -0.884 N

 

Qhov tshwm sim ntawm ob lub zog no yog 5.7 N.

2. F₁ = 4 N, F₂ = 4 N, F₃ = 8 N. Txheeb xyuas qhov vector uas tau txais.

tshuaj

F_1x =F₁ coj 60^o = (4)(0.5) = 2 N (zoo vim nws muaj tib qho kev taw qhia li x axis)

F_2x = -4 N (tsis zoo vim nws muaj tib qho kev taw qhia li -x axis)

F_3x =F₃ coj 60^o = (8)(0.5) = 4 N (zoo vim nws muaj tib qho kev taw qhia li x axis)

F_1y =F₁ kev txhaum 60^o = (4)(0.5√3) = 2√3 N (zoo vim nws muaj tib qho kev taw qhia li y axis)

F_2y = 0

F_3y =F₃ kev txhaum 60^o = (8)(0.5√3) = -4√3 N (tsis zoo) vim nws muaj tib qho kev taw qhia li -y axis)

F_x =F_1x - F_2x +F_3x = 2 – 4 + 4 = 2 N

F_y =F_1y +F_2y - F_3y = 2√3 + 0 – 4√3 = -2√3 N

Qhov tshwm sim ntawm peb lub zog no yog 5.7 N.

[wpdm_package id='542′]

[wpdm_package id='554′]

1. Txheeb xyuas qhov tshwm sim ntawm hauv kab vector
2. Txheeb xyuas cov khoom sib xyaw vector
3. Txheeb xyuas qhov tshwm sim ntawm ob lub vectors siv Pythagorean theorem
4. Txheeb xyuas qhov tshwm sim ntawm ob lub vectors siv cov qauv cosines
5. Txheeb xyuas qhov tshwm sim ntawm ob lub vectors siv cov khoom ntawm vectors

nyeem ntxiv

Tau daws cov teeb meem hauv vectors - txiav txim siab qhov tshwm sim ntawm ob lub vectors siv cov qauv cosines

1. F₁ = 10 N thiab F₂ = 20 N. Txheeb xyuas qhov vector uas tau txais.

2. A₁ = 15 thiab A₂ = 9. Lub kaum sab xis ntawm ob lub vectors yog 60^oTxheeb xyuas qhov vector uas tau los.

tshuaj

3. v₁ = 5 thiab v₂ = 12. Lub kaum sab xis ntawm ob lub vectors yog 90^oTxheeb xyuas qhov vector uas tau los.

tshuaj

[wpdm_package id='542′]

[wpdm_package id='554′]

1. Txheeb xyuas qhov tshwm sim ntawm hauv kab vector
2. Txheeb xyuas cov khoom sib xyaw vector
3. Txheeb xyuas qhov tshwm sim ntawm ob lub vectors siv Pythagorean theorem
4. Txheeb xyuas qhov tshwm sim ntawm ob lub vectors siv cov qauv cosines
5. Txheeb xyuas qhov tshwm sim ntawm ob lub vectors siv cov khoom ntawm vectors

nyeem ntxiv

Tau daws cov teeb meem hauv vectors - txiav txim siab qhov tshwm sim ntawm ob lub vectors siv Pythagorean theorem

1. Txheeb xyuas qhov tshwm sim ntawm ob qho xaav cov vectors raws li qhia hauv daim duab hauv qab no.

2. Nrhiav tus ua los ntawm ob lub zog, 12 N thiab 5 N.

3. Ib tug tub ntxhais kawm taug kev 4 meters mus rau sab hnub poob, tom qab ntawd 6 meters mus rau sab qaum teb thiab 4 meters mus rau sab hnub poob. Nrhiav qhov kev hloov chaw ntawm tus tub ntxhais kawm.

tshuaj

Kev hloov chaw yog 10 mepeb, mus rau sab qaum teb sab hnub poob.

[wpdm_package id='542′]

[wpdm_package id='554′]

1. Txheeb xyuas qhov tshwm sim ntawm hauv kab vector
2. Txheeb xyuas cov khoom sib xyaw vector
3. Txheeb xyuas qhov tshwm sim ntawm ob lub vectors siv Pythagorean theorem
4. Txheeb xyuas qhov tshwm sim ntawm ob lub vectors siv cov qauv cosines
5. Txheeb xyuas qhov tshwm sim ntawm ob lub vectors siv cov khoom ntawm vectors

nyeem ntxiv

Tau daws cov teeb meem hauv vectors - txiav txim siab cov khoom sib xyaw vector

1. Lub zog ntawm 20 Newtons ua rau lub kaum sab xis ntawm 30^o nrog rau x-axis. Nrhiav ob qho x thiab y Cheebtsam ntawm lub zog.

tshuaj

F_x = F cos 30^o = (20)(cos 30^o) = (20)(0.5√3= 10 TZS√3 Newton

F_y = F txhaum 30^o = (20)(kev txhaum 30^o) = (20)(0.5) = 10 Newtons

2. F₁ = 20 Newtons ua rau lub kaum sab xis yog 30^o nrog rau y axis thiab F axis₂ = 30 Newtons ua rau lub kaum sab xis yog 60^o nrog rau -x axis. Nrhiav ob qho x thiab y Cheebtsam ntawm F₁ thiab F₂.

tshuaj

F_1x =F₁ cos 60^o = (20)(cos 60^o) = (20)(0.5) = -10 Newtons (tsis zoo vim nws muaj tib qho kev taw qhia li -x axis)

F_2x =F₂ cos 60^o = (30)(cos 60^o) = (30)(0.5) = -15 Newtons (tsis zoo vim nws muaj tib qho kev taw qhia li -x axis)

F_1y =F₁ kev txhaum 60^o = (20)(kev txhaum 60^o) = (20)(0.5√3= 10 TZS√3 Newton (zoo vim nws muaj tib qho kev taw qhia li y axis)

F_2y =F₂ kev txhaum 60^o = (30)(kev txhaum 60^o) = (30)(0.5√3) = -15√3 Newton (tsis zoo vim nws muaj tib qho kev taw qhia li -y axis)

3. F₁ = 2 N, F₂ = 4 N, F₃ = 6 N. Nrhiav ob qho x thiab y ntawm F₁, F₂ thiab F₃!

tshuaj

F_1x =F₁ cos 60^o = (2)(cos 60^o) = (2)(0.5) = 1 Newton (zoo vim nws muaj tib qho kev taw qhia nrog x axis)

F_2x =F₂ cos 30^o = (4)(cos 30^o) = (4)(0.5√3) = -2√3 Newton (tsis zoo vim nws muaj tib qho kev taw qhia nrog -x axis)

F_3x =F₃ cos 60^o = (6)(cos 60^o) = (6)(0.5) = 3 Newton (zoo vim nws muaj tib qho kev taw qhia nrog x axis)

F_1y =F₁ kev txhaum 60^o = (2)(kev txhaum 60^o) = (2)(0.5√3) = √3 Newton (zoo vim nws muaj tib qho kev taw qhia li y axis)

F_2y =F₂ kev txhaum 30^o = (4)(kev txhaum 30^o) = (4)(0.5) = 2 Newtons (zoo vim nws muaj tib qho kev taw qhia nrog y axis)

F_3y =F₃ kev txhaum 60^o = (6)(kev txhaum 60^o) = (6)(0.5√3) = -3√3 Newton (tsis zoo vim nws muaj tib qho kev taw qhia nrog -y axis)

[wpdm_package id='542′]

[wpdm_package id='554′]

1. Txheeb xyuas qhov tshwm sim ntawm hauv kab vector
2. Txheeb xyuas cov khoom sib xyaw vector
3. Txheeb xyuas qhov tshwm sim ntawm ob lub vectors siv Pythagorean theorem
4. Txheeb xyuas qhov tshwm sim ntawm ob lub vectors siv cov qauv cosines
5. Txheeb xyuas qhov tshwm sim ntawm ob lub vectors siv cov khoom ntawm vectors

nyeem ntxiv

Tau daws cov teeb meem hauv vectors - qhov tshwm sim ntawm hauv kab vector

1. Ib tug tub ntxhais kawm taug kev mus rau sab qaum teb mus txog 10 meters thiab tom qab ntawd mus rau sab qab teb mus txog 4 meters. Kev tshem tawm ntawm tus tub ntxhais kawm yog…

tshuaj

R = 10 m – 4 m = 6 meters

Qhov loj ntawm xaav yog 6 meters, qhov kev taw qhia ntawm kev hloov chaw yog sab qaum teb.

2. F₁ = 10 N, F₂ = 15 N. Txheeb xyuas qhov vector uas tau tshwm sim ...

tshuaj

R = 10 N + 15 N = 25 Newtons

Qhov loj ntawm cov vector tshwm sim yog 25 Newtons, qhov kev taw qhia ntawm cov vector tshwm sim yog sab hnub tuaj lossis sab xis.

3. F₁ = 4 N, F₂ = 8 N. Txheeb xyuas qhov vector uas tau tshwm sim ...

tshuaj

R = 8 N – 4 N = 4 Newton

Qhov loj ntawm cov vector tshwm sim yog 4 Newtons, qhov kev taw qhia ntawm cov vector tshwm sim yog sab hnub tuaj lossis sab xis.

4. F₁ = 10, F₂ = 15 N, F₃ = 5 N. Txheeb xyuas qhov vector uas tau tshwm sim ...

tshuaj

R = 10 N + 5 N – 15 N = 0

Qhov loj ntawm cov vector resultant yog 0.

[wpdm_package id='542′]

[wpdm_package id='554′]

1. Txheeb xyuas qhov tshwm sim ntawm hauv kab vector
2. Txheeb xyuas cov khoom sib xyaw vector
3. Txheeb xyuas qhov tshwm sim ntawm ob lub vectors siv Pythagorean theorem
4. Txheeb xyuas qhov tshwm sim ntawm ob lub vectors siv cov qauv cosines
5. Txheeb xyuas qhov tshwm sim ntawm ob lub vectors siv cov khoom ntawm vectors

nyeem ntxiv