Kuyenda movutikira - mavuto ndi njira zothetsera mavuto

Kuyenda movutikira - mavuto ndi njira zothetsera mavuto

1. Misa buloko ndi 5 kg, kuthamanga chifukwa cha mphamvu yokoka = 9.8 m/s², tan 37 ^o = 3/4. Kodi kuthamanga kwa chipikacho ndi chiyani?

Anakonza

Zodziwika:

kulemera (m) = 5 kg

kuthamanga chifukwa cha mphamvu yokoka (g) = 10 m/s²

kulemera (w) = mg = (5)(10) = 50 N

x = 3

Kutalika kwa ndege yopendekera (y) = 4

Kutalika kwa malo otsetsereka (l) = 5

anafuna : kuthamanga ya buloko (a) ?

Yankho:

Chipikacho chimafulumizitsidwa ndi mphamvu ya w_x. Malo otsetsereka ndi osalala kotero palibe mphamvu yokangana.

w_x = w sin θ = (w)(y / z)

w_x = (50)(4/5)

w_x = 40 Newton

Kuthamanga kwa chipika (a) ?

ΣF = ma

w_x = ma

40 = (5) a

a = 40 / 5

a = 8 m/s²

2. Choyambira chikakhala pamalo opumulira, kenako chimapita patsogolo motsatizana ndi malo otsetsereka. Kulemera kwa chogwirira = 8 kg, coefficient of static friction µ_s = 0.5 ndi ngodya θ = 45^oKodi mphamvu ya F ndi yotani kuti chipikacho chifulumizitsidwe?

Zodziwika:

Koyenera ya kukangana kosasinthasintha (µ)_s= = 0.5

Ngodya (θ) = 45^o

Kuthamanga chifukwa cha mphamvu yokoka (g) = 10 m/s²

Kulemera kwa Block (m) = 8 kg

Kulemera kwa chipika (w) = mg = (8 kg)(10 m/s²) = 80 kg m/s² = 80 Newton

Kufunidwa: Kukula kwa mphamvu F

Yankho:

Block yambani kuthamangitsa ngati F ≥ w_x + f_s.

Chigawo cholemera chopingasa :

w_x = w uchimo θ = (80)(tchimo 45) = (80)(0.5√2) = 40√2

Chigawo cholemera cha kulemera:

w_y = w cos θ = (80)(cos 45) = (80)(0.5√2) = 40√2

mphamvu yachibadwa :

N = w_y = 40√2

Mphamvu ya kukangana kosasinthasintha:

f_s = µ_s N = (0.5)(40√2) = 20√2

Kukula kwa mphamvu F:

F ≥ w_x + f_s

F ≥ 40√2 + 20√2

F ≥ 60√2 Newton

3. Kulemera kwa chipikacho ndi 8 kg. Mphamvu yochepa yofunikira kuti munthu agwire chotsani so kuti chipikacho osati slides pansi ndi ...(tchimo 37^o = 0.6, cos 37^o = 0.8, g = 10 ms^-2, µ_k = 0.1)

Zodziwika:

Kulemera kwa chipika (m) = 8 kg

Kuthamanga chifukwa cha mphamvu yokoka (g) = 10 m/s²

Kulemera kwa chipika (w) = mg = (8)(10) = 80 Newtons

Tchimo 37^o = 0.6

kodi 37^o = 0.8

Koyenera ya kukangana kwa kinetic (µ_k= = 0.1

Mphamvu yachibadwa (N) = w_y = w cos 37^o = (80)(0.8) = 64 Newtons

Akufuna: Kukula kwa mphamvu F

Yankho:

Chipikacho sichimatsika pansi ngati F = w_x

Gawo lopingasa la kulemera lofanana ndi pamwamba pake:

w_x = w uchimo θ = (80)(tchimo 37) = (80)(0.6) = 48

f_k = µ_k N = (0.1)(64) = 6.4

Mphamvu yochepa F kuti chipikacho chisagwere pansi:

F + f_k - w_x = 0

F = w_x - f_k = 48 – 6.4 = 41.6 Newtons

4. Chipolopolo cha makilogalamu 5 chimakokedwa mozungulira mopingasa ndi mphamvu ya 71 N (g = 10 ms).^-2, uchimo 37^o = 0.6, cos 37^o = 0.8). Ngati mphamvu yokwanira pakati pa block ndi plane yopendekera ndi 0.4, kodi kuthamanga kwa block ndi kotani?

Zodziwika:

Kulemera kwa chinthu (m) = 5 kg

Kuthamanga chifukwa cha mphamvu yokoka (g) = 10 m/s²

kulemera kwa chipika (w) = mg = (5)(10) = 50 Newtons

Mphamvu F = 71 Newton

Tchimo 37^o = 0.6

kodi 37^o = 0.8

Koyenera ya kukangana = 0.4

anafuna Kuthamanga kwa chipika (a)

Yankho:

Chigawo cholemera chopingasa :

w_x = w uchimo θ = (50)(tchimo 37) = (50)(0.6) = 30

Chigawo cholemera choyima :

w_y = w cos θ = (50)(cos 37) = (50)(0.8) = 40

Mphamvu yachibadwa:

N = w_y = 40

Mphamvu ya kukangana kwa kinetic:

f_k = µ_k N = (0.4)(40) = 16

Mphamvu ya intaneti:

∑F = F – w_x - f_k = 71 – 30 – 16 = 25 Newtons

Kufulumizitsa chinthucho:

a = ∑F / m = 25 / 5 = 5 m/s²

5. Bokosi la 500-N lokwezedwa ku galimoto kudzera mu mtunda wopendekeka, monga momwe chithunzi chili pansipa chikusonyezera. Ngati kutalika kwa galimoto ndi mamita 1.5, dziwani kukula kwa mphamvu yosunthira bokosilo.

Zodziwika:

kulemera kwa bokosi (w) = 500 Newtons

kutalika kwa galimoto (h) = mamita 1.5

kutalika kwa ndege yopendekeka (l) = mamita atatu

Akufuna: Mphamvu yosuntha bokosi (F)

Yankho:

Sin θ = opp / hyp = 1.5 mamita / 3 mamita = 1.5 / 3 = 0.5

Mphamvu (F) yofunikira kuti bokosilo lisunthe, mofanana ndi gawo lopingasa la kulemera lomwe lili lofanana ndi ndege yopendekera (w)_x).

w_x = w uchimo θ = (500 N)(0.5) = 250 N

1. Kodi ndege yopendekeka ndi chiyani, ndipo imapangitsa bwanji kuti ntchito ikhale yosavuta?
   • yankho: Malo otsetsereka ndi malo athyathyathya omwe ali pa ngodya (kupatula ngodya yakumanja) kulowera pamalo opingasa. Zimapangitsa ntchito kukhala yosavuta mwa kulola mphamvu kugwiritsidwa ntchito patali kuti igonjetse mphamvu yotsutsa, nthawi zambiri kuchepetsa kukula kwa mphamvu yofunikira kukweza kapena kutsitsa chinthu.
2. Kodi ngodya ya kupendekera imakhudza bwanji mphamvu yofunikira kuti chinthu chiyendetsedwe mmwamba?
   • yankho: Ngodya yopendekera ikakwera kwambiri, mphamvu yofunikira kuti chinthu chiyende mmwamba imakhala yayikulu. Ngodya ikachepa, mphamvu yofunikira imachepa koma imagwiritsidwa ntchito patali kwambiri.
3. N’chifukwa chiyani n’kosavuta kukankhira bokosi lolemera m’mwamba kuposa kulikweza molunjika?
   • yankho: Kukankhira bokosi mmwamba pa ramp (mzere wopendekera) kumagawa kulemera kwa bokosilo patali kwambiri, kuchepetsa mphamvu yofunikira nthawi iliyonse. Kulikweza molunjika kumafuna kuti munthu athane ndi kulemera konse kwa bokosilo mwachindunji, zomwe zimafuna mphamvu yayikulu kwambiri.
4. Kodi kutalika kwa ndege yopendekeka kukugwirizana bwanji ndi mphamvu yofunikira kuti chinthu chiyendetsedwe mmwamba?
   • yankho: Kutalika kwa malo otsetsereka (kuti munthu akhale ndi kutalika kokhazikika), mphamvu yochepa imafunika kuti chinthu chiyende mmwamba. Komabe, mphamvuyo iyenera kugwiritsidwa ntchito patali kwambiri.
5. Ngati kukangana kwachitika pamalo opendekeka, kodi kumakhudza bwanji kayendedwe ka chinthu chomwe chili pamenepo?
   • yankhoKukangana kumatsutsana ndi kuyenda kwa chinthucho. Ngati chinthu chikukankhidwira mmwamba pa malo opendekeka, kukangana kumatsika, zomwe zimawonjezera mphamvu yofunikira kuti chinthucho chisunthike. Ngati chinthu chikuyenda pansi pa malo opendekeka, kukangana kumachedwetsa kutsika kwake.
6. N’chifukwa chiyani antchito amagwiritsa ntchito ndege zopendekera kukweza katundu wolemera m’malole?
   • yankhoKugwiritsa ntchito njira yolunjika (ramp) kumathandiza ogwira ntchito kugwiritsa ntchito mphamvu zochepa pa mtunda wautali kuti anyamule zinthu zolemera, zomwe zimapangitsa kuti ntchitoyi ikhale yosavuta komanso yosavuta kuposa kunyamula zinthuzo moyima.
7. Kodi kulemera kwa chinthu kumagwirizana bwanji ndi chizolowezi chake chotsetsereka pansi mopendekeka?
   • yankho: Chigawo cha kulemera kwa chinthucho chomwe chimagwira ntchito molingana ndi pamwamba pa malo opendekera chimapangitsa kuti chigwedezeke. Chinthucho chikalemera kwambiri, chimapangitsa kuti chigwedezeke kwambiri, motero, chimapangitsa kuti chinthucho chigwedezeke kwambiri.
8. Kodi mphamvu yachibadwa imagwira ntchito yotani pa malo otsetsereka?
   • yankhoMphamvu yachibadwa imagwira ntchito molunjika pamwamba pa ndege yopendekeka. Ndi yomwe imayang'anira kuchuluka kwa mphamvu yokangana pakati pa chinthucho ndi ndegeyo chifukwa kukangana nthawi zambiri kumakhala kofanana ndi mphamvu yachibadwa.
9. N’chifukwa chiyani mchenga kapena phulusa zingaikidwe pamalo otsetsereka pamene kuli chisanu?
   • yankho: Mchenga kapena grit zimawonjezera mphamvu yokangana pakati pa malo otsetsereka ndi zinthu (monga nsapato kapena matayala) zomwe zakhudzana nazo. Kukangana kowonjezera kumeneku kumathandiza kupewa kutsetsereka panthawi yozizira kapena yonyowa.
10. Ngati mpira wakulungidwa mmwamba mopendekeka kenako n’kubwerera pansi, kodi udzafika pa liwiro lake loyambirira pofika nthawi yomwe udzabwerera kumene unayambira, osanyalanyaza kukana kwa mpweya ndi kukangana?

• yankhoInde, popanda kukana kwa mpweya ndi kukangana, mphamvu zomwe mpira ungathe kupirira pamalo ake apamwamba zidzasanduka mphamvu ya kinetic ikatsika, zomwe zimathandiza kuti ufike pa liwiro lake loyambirira pofika nthawi yomwe ubwerera komwe umayambira chifukwa cha kusunga mphamvu.