Cov duab ntawm kev txav mus los linear - teeb meem thiab kev daws teeb meem

1. Kos duab qhov deb (ntsug) piv rau lub sijhawm (kab rov tav) raws li pom hauv daim duab hauv qab no. Ib yam khoom uas so tau qhia los ntawm tus lej…

Tshuaj:

Cov duab ntawm kev txav mus los linear - teeb meem thiab kev daws teeb meem 1

Tus lej 3, qhia los ntawm ib txoj kab ncaj.

2. Qhov ceev ntawm daim duab (ntsug) piv rau lub sijhawm (kab rov tav) ntawm kev txav mus los ntawm kev nrawm tas li . Qhov loj ntawm qhov kev nrawm raws li daim duab yog dab tsi?

Tshuaj:

Cov duab ntawm kev txav mus los linear - teeb meem thiab kev daws teeb meem 3

3. Ib tug neeg tau caij tsheb los ntawm lub nroog A mus rau lub nroog B, raws li daim duab hauv qab no. Kab ntsug yog qhov ceev thiab kab kab rov tav yog lub sijhawm. Lub tsheb tau mus deb npaum li cas thaum 30 feeb txog 60 feeb.

Paub: Cov duab ntawm kev txav mus los linear - teeb meem thiab kev daws teeb meem 4

Qhov ceev (v) = 40 km/h

Lub Sijhawm Sib Npaug (t) = 60 – 30 = 30 feeb = 0.5 teev

Xav Tau: Qhov Deb

Tshuaj:

Qhov nrug = qhov ceev x lub sijhawm

Qhov Nrug Deb = (40 km/teev)(0.5 teev)

Qhov Nrug Deb = 20 km

4. Daim duab qhia txog qhov ceev (kab ntsug) piv rau lub sijhawm (kab kab rov tav) qhia txog kev txav ntawm lub tsheb txij thaum so ces txav mus txog thaum nres rau 8 vib nas this, raws li pom hauv daim duab hauv qab no.

Cov duab ntawm kev txav mus los linear - teeb meem thiab kev daws teeb meem 5

Lub tsheb khiav deb npaum li cas los ntawm 5 vib nas this mus rau 8 vib nas this?

Tshuaj:

Cheeb Tsam 1 = cheeb tsam ntawm daim duab peb ceg CD = ½ (6-5)(40-20) = ½ (1)(20) = 10

luas 2 = luas daim duab peb sab DE = ½ (8-6)(20-0) = ½ (2)(20) = 20

Cheeb Tsam 3 = Cheeb Tsam ntawm lub xwmfab = (6-5)(20-0) = (1)(20) = 20

Qhov deb uas lub tsheb taug kev los ntawm 5 vib nas this mus rau 8 vib nas this = 10 + 20 + 20 = 50 meters.

5. Qhov deb ntawm 5 vib nas this kawg raws li daim duab hauv qab no yog ....

Cov duab ntawm kev txav mus los linear - teeb meem thiab kev daws teeb meem 6

Tshuaj:

Cheeb Tsam 1 = cheeb tsam ntawm daim duab peb sab = ½ (6-5)(40-20) = ½ (1)(20) = 10

Cheeb Tsam 2 = cheeb tsam ntawm lub duab plaub fab = (9-5)(20-0) = (4)(20) = 80

Cheeb Tsam 3 = cheeb tsam ntawm daim duab peb sab = ½ (10-9)(20-0) = ½ (1)(20) = 10

Qhov deb ntawm 5 vib nas this kawg :

10 + 80 + 10 = 100 meters

6. Daim duab qhia qhov ceev piv rau lub sijhawm ntawm kev txav mus los tsis sib xws ntawm lub tsheb.

Qhov kev nrawm tib yam tshwm sim ntawm… Cov duab ntawm kev txav mus los linear - teeb meem thiab kev daws teeb meem 7

Tshuaj:

vt ₌ v0 ₊ at

v _t – v _o = at

a = vt _– vo _/ t

a = kev nrawm, v _t = qhov ceev kawg, v _o = qhov ceev pib, t = lub sijhawm luv.

Kev nrawm AB = (25 – 20) / (20 – 0) = 5 / 20 = 1/4 = 0.25 m/s ²

Kev nrawm BC = (45 – 25) / (40 – 20) = 20 / 20 = 1 m/s ²

Kev nrawm CD = (35 – 45) / (50 – 40) = 10 / 10 = 1 m/s ²

Kev nrawm DE = (25 – 35) / (70 – 50) = 10 / 20 = 1/2 = 0.5 m/s ²

Kev nrawm EF = (0 – 25) / (90 – 70) = 25 / 20 = 5/4 = 1.25 m/s ²

7. Qhov deb uas taug kev hauv 10 vib nas this yog dab tsi?

Paub:

Qhov ceev pib (v_o= 0 TZS Cov duab ntawm kev txav mus los linear - teeb meem thiab kev daws teeb meem 8

Qhov ceev kawg (v _t ) = 20 m/s

Lub sijhawm luv (t) = 4 vib nas this

Xav tau:

Qhov deb tau mus txog hauv 10 vib nas this

Tshuaj:

Peb qhov kev sib npaug ntawm kev txav mus los ntawm qhov kev nrawm tas mus li:

vt ₌ v0 ₊ at

d = v _ot + ½ ntawm ²

v _t² = v _o² + 2 ad

v _t = qhov ceev kawg, v _o = qhov ceev pib, a = kev nrawm, t = lub sijhawm luv, d = qhov deb

Kev nrawm (a):

vt ₌ v0 ₊ at

20 = 0 + ib (4)

20 = 4 ib

ib = 20 / 4

a = 5 m/s ²

Qhov deb tau mus txog hauv 10 vib nas this:

d = v _ot + ½ ntawm ²

d = (0)(10) + ½ (5)(10) ²

d = ½ (5)(100)

d = (5)(50)

d = 250 meters

8. Yog tias ib yam khoom raug pov ntsug rau saum npoo av, ces qhov twg yog daim duab ntawm kev nrawm uas yam khoom ntawd ntsib.

Daim duab qhia txog cov teeb meem kev txav mus los thiab kev daws teeb meem 1

tshuaj

Thaum ib yam khoom txav mus rau saum ntuj, qhov kev nrawm uas ib yam khoom ntsib yog kev nrawm vim lub ntiajteb txawj nqus. Qhov loj ntawm kev nrawm vim lub ntiajteb txawj nqus yog 9.8 m/s ² thiab qhov kev nrawm vim lub ntiajteb txawj nqus yog mus rau hauv nruab nrab ntawm lub ntiaj teb.

Qhov kev nrawm nrawm tas li yog tus cwj pwm los ntawm ib txoj kab ncaj nraim mus rau t axis thiab perpendicular mus rau a axis.

Cov lus teb yog D.

9. Raws li daim duab hauv qab no, txiav txim seb yam khoom ntawd mus deb npaum li cas rau 20 vib nas this.

A. 600 m Daim duab qhia txog cov teeb meem kev txav mus los thiab kev daws teeb meem 2

B. 500 m

C. 200 m

D. 100 m

tshuaj

Qhov deb mus ncig thaum 0 - 10 vib nas this = thaj tsam ntawm lub xwmfab + thaj tsam ntawm daim duab peb sab

Thaj tsam ntawm lub xwmfab = (20-0)(10-0) = (20)(10) = 200 meters

Thaj tsam ntawm daim duab peb sab = (1/2)(10-0)(40-20) = (1/2)(10)(20) = (5)(20) = 100 meters

Qhov deb tau mus ncig thaum 0 - 10 vib nas this = 200 meters + 100 meters = 300 meters

Qhov deb mus ncig thaum 10 - 20 vib nas this = thaj tsam ntawm daim duab peb sab

Thaj tsam ntawm daim duab peb sab = (1/2)(20-10)(40-0) = (1/2)(10)(40) = (5)(40) = 200 meters

Qhov deb tau mus ncig thaum 0 - 20 vib nas this:

300 meters + 200 meters = 500 meters

Cov lus teb yog B.

10. Kev txav ntawm peb yam khoom, txhua yam tau piav qhia los ntawm daim duab hauv qab no.

Daim duab qhia txog cov teeb meem kev txav mus los thiab kev daws teeb meem 3

Txheeb xyuas cov lus hais kom raug rau kev txav ntawm tag nrho peb yam khoom.

Daim duab qhia txog cov teeb meem kev txav mus los thiab kev daws teeb meem 4

Tshuaj:

Daim duab ntawm yam khoom 1 = Daim duab ntawm kev nrawm (a) thiab lub sijhawm luv (t)

Raws li daim duab graph, yam khoom txav mus los ntawm qhov kev nrawm tas li. Qhov kev nrawm tas li qhia los ntawm ib txoj kab ncaj nraim perpendicular rau lub axis ntawm kev nrawm (a).

Daim duab ntawm yam khoom 2 = Daim duab ntawm qhov ceev (v) thiab lub sijhawm luv (a)

Raws li daim duab graph, yam khoom txav mus rau qhov ceev tas li. Qhov ceev tas li qhia los ntawm ib txoj kab ncaj nraim perpendicular rau lub axis ntawm qhov ceev (v).

Daim duab ntawm yam khoom 3 = Daim duab ntawm kev hloov chaw (x) thiab lub sijhawm (a)

Raws li daim duab graph, qhov hloov chaw tas mus li lossis yam khoom so.

Cov lus teb yog lawm yog A.

11. Qhov chaw ntawm ib yam khoom uas txav mus raws txoj kab x yog qhia los ntawm daim duab hauv qab no.

Daim duab qhia txog cov teeb meem kev txav mus los thiab kev daws teeb meem 5

Daim duab qhia tau hais tias yam khoom txav mus los ntawm qhov ceev tas li ntawm lub sijhawm sib txawv….

A. 5-15 vib nas this thiab 25-35 vib nas this

B. 0-5 vib nas this thiab 35-40 vib nas this

C. 15-25 vib nas this

D. 0-5 vib nas this, 15-25 vib nas this thiab 35-40 vib nas this

Tshuaj:

5-15 vib nas this thiab 25-35 vib nas this = Qhov khoom txav mus tas li lossis qhov khoom so.

0-5 vib nas this, 15-25 vib nas this thiab 35-40 vib nas this = khoom txav mus rau qhov ceev tas li.

Cov lus teb yog D.

12. Daim duab hauv qab no qhia txog qhov ceev ntawm lub sijhawm ua haujlwm ntawm ob yam khoom txav mus ncaj qha los ntawm tib qho chaw pib. Tom qab txav mus rau t vib nas this ob yam khoom muaj tib qho chaw hloov pauv. Txheeb xyuas lub sijhawm thiab kev hloov chaw ntawm yam khoom.

A. 5 vib nas this thiab 50 meters Daim duab qhia txog cov teeb meem kev txav mus los thiab kev daws teeb meem 6

B. 5 vib nas this thiab 100 meters

C. 10 vib nas this thiab 50 meters

D. 10 vib nas this thiab 100 meters

Tshuaj:

Daim Duab 1 = kev nrawm tas mus li

Lub sijhawm sib nrug = 10 vib nas this

Qhov Nrug Deb = thaj tsam ntawm daim duab peb sab = ½ (v)(t) = ½ (10-0)(20-0) = ½ (10)(20) = (5)(20) = 100 meters

Daim Duab 2 = qhov ceev tas mus li

Lub sijhawm sib nrug = 10 vib nas this

Qhov Nrug = thaj tsam ntawm lub xwmfab = (v)(t) = (10-0)(10-0) = (10)(10) = 100 meters

Cov lus teb yog D.

13. Raws li daim duab hauv qab no, lub sijhawm thaum lub khoom txav mus los ntawm qhov nrawm tas li thiab lub sijhawm thaum lub khoom muaj kev nrawm tshaj plaws yog ....

A. Nruab nrab ntawm 0 thiab t₁, thiab ntawm t₁ thiab t₂

B. Nruab nrab ntawm t ₁ thiab t ₂ , thiab nruab nrab ntawm t ₂ thiab t ₃

C. Nruab nrab ntawm t ₂ thiab t ₃ , thiab nruab nrab ntawm t ₁ thiab t ₂

D. Nruab nrab ntawm 0 thiab t ₁ , thiab nruab nrab ntawm t ₂ thiab t ₃

Tshuaj:

Yog daim duab yog ib txoj kab ncaj ces qhov ceev yog qhov ruaj khov, yog daim duab yog ib txoj kab txiav ces qhov kev nrawm yog qhov ruaj khov. Txoj kab tab tom tig, qhov kev nrawm loj zuj zus.

0 – t ₁ = kev nrawm tas mus li

t ₁ – t ₂ = qhov ceev tas li

t ₂ – t ₃ = kev nrawm tas mus li

Cov lus teb yog B.

1. Lo lus nug: Qhov nqes hav ntawm daim duab qhia chaw thiab lub sijhawm sawv cev rau dab tsi? Lus teb: Qhov nqes hav ntawm daim duab qhia chaw thiab lub sijhawm sawv cev rau qhov ceev ntawm yam khoom. Qhov nqes hav ntxhab qhia txog qhov ceev siab dua, thaum txoj kab tiaj tiaj (kab rov tav) qhia tias yam khoom nyob twj ywm.

2. Lo lus nug: Ntawm daim duab qhia txog qhov ceev thiab lub sijhawm, koj txiav txim siab li cas qhov kev hloov chaw ntawm ib yam khoom? Lus teb: Qhov kev hloov chaw ntawm ib yam khoom tuaj yeem nrhiav tau los ntawm kev xam thaj tsam hauv qab qhov nkhaus (lossis ntawm qhov nkhaus thiab x-axis) ntawm daim duab qhia txog qhov ceev thiab lub sijhawm.

3. Lo lus nug: Koj yuav ua li cas thiaj paub qhov txawv ntawm kev txav mus los sib npaug thiab tsis sib npaug ntawm daim duab qhia chaw thiab lub sijhawm? Lus teb: Hauv daim duab qhia chaw thiab lub sijhawm, kev txav mus los sib npaug yog sawv cev los ntawm ib txoj kab ncaj (qhov nqes tas li), thaum kev txav mus los tsis sib npaug yog piav qhia los ntawm ib txoj kab nkhaus, qhia tias qhov ceev hloov pauv raws sijhawm.

4. Lo lus nug: Kab kab rov tav ntawm daim duab qhia txog qhov ceev piv rau lub sijhawm qhia txog dab tsi? Lus teb: Kab kab rov tav ntawm daim duab qhia txog qhov ceev piv rau lub sijhawm qhia tias yam khoom txav mus nrog qhov ceev tas li, piv txwv li, nws tsis nrawm lossis qeeb.

5. Lo lus nug: Yog tias daim duab qhia txog qhov ceev thiab lub sijhawm nyob hauv qab lub sijhawm (qhov ceev tsis zoo), nws txhais li cas? Lus teb: Yog tias daim duab qhia txog qhov ceev thiab lub sijhawm nyob hauv qab lub sijhawm, nws qhia tias yam khoom txav mus rau qhov kev taw qhia txawv ntawm qhov kev taw qhia siv (feem ntau suav tias yog qhov zoo).

6. Lo lus nug: Kev nrawm nrawm sawv cev li cas rau ntawm daim duab qhia txog kev nrawm piv rau lub sijhawm? Lus teb: Ntawm daim duab qhia txog kev nrawm piv rau lub sijhawm, kev nrawm nrawm yog sawv cev los ntawm qhov nqes hav ntawm daim duab. Qhov nqes hav zoo qhia txog kev nrawm zoo, qhov nqes hav tsis zoo qhia txog kev nrawm tsis zoo (lossis kev qeeb qeeb), thiab kab tiaj tiaj qhia txog kev nrawm tsis muaj.

7. Lo lus nug: Ib daim duab parabolic ntawm daim duab qhia txog qhov chaw piv rau lub sijhawm qhia txog dab tsi? Lus teb: Ib daim duab parabolic ntawm daim duab qhia txog qhov chaw piv rau lub sijhawm qhia tias yam khoom nyob hauv qab qhov kev nrawm tas li. Cov duab ntawm daim duab yog quadratic, sib xws nrog cov kab zauv kinematic $s = v o t + 1/2 a t^{2}$ .

8. Lo lus nug: Hauv daim duab qhia txog qhov chaw piv rau lub sijhawm, koj yuav txiav txim siab li cas yog tias ib yam khoom txav mus tom ntej lossis rov qab piv rau nws qhov chaw pib? Lus teb: Yog tias daim duab qhia txog qhov chaw piv rau lub sijhawm nce (txav mus rau saum toj), nws qhia tias yam khoom txav mus tom ntej (lossis mus rau qhov zoo). Yog tias daim duab qhia txog qhov chaw lossis kab nqes (txav mus rau hauv qab), nws qhia tias yam khoom txav mus tom qab (lossis mus rau qhov tsis zoo) piv rau nws qhov chaw pib.

9. Lo lus nug: Ib yam khoom poob dawb zoo li cas ntawm daim duab qhia qhov ceev piv rau lub sijhawm? Lus teb: Rau ib yam khoom poob dawb (tsis quav ntsej txog kev tiv thaiv ntawm huab cua), daim duab qhia qhov ceev piv rau lub sijhawm yuav yog ib txoj kab ncaj nraim nrog lub nqes hav zoo (yog tias pib ntawm so) vim yog qhov kev nrawm tas li vim yog lub ntiajteb txawj nqus. Lub nqes hav yuav sawv cev rau tus nqi nrawm, uas ntawm lub ntiaj teb yog kwv yees li $9.8 m / s^{2}$ .

10. Lo lus nug: Yog tias ib yam khoom so, nws daim duab qhia txog kev nrawm piv rau lub sijhawm yuav zoo li cas? Lus teb: Rau ib yam khoom so, nws daim duab qhia txog kev nrawm piv rau lub sijhawm yuav yog ib txoj kab kab rov tav ntawm lub sijhawm, qhia tias kev nrawm yog xoom thoob plaws lub sijhawm.