Fomula yamphamvu pa ndege yopendekeka

Zitsanzo za mafunso ndi njira za mphamvu zomwe zili m'ndege zopendekera

1. Mphamvu yokhazikika yopingasa ya kukula kwa 50 N imagwira ntchito pa chipika chokhala ndi kulemera kwa m = 5 kg. Chipilacho chimapita mmwamba ndi liwiro loyambirira v._o = 4 m/s motsatira mzere wozungulira mozungulira wokhala ndi ngodya yopendekera θ (utoto wachikasu Koefficient = ¾). θ = ¾). kukangana kwa kayendedwe ka kayendedwe kake pakati pa chipika ndi pamwamba pa ndege yopendekera ndi μ_k = 0,2. Mtunda woyenda ndi bwalo lisanayime ndi…

A. 10 m

B. 12 m

C. 15 m

D. 18 m

E. 22 m

w = mphamvu yokoka

w_x = gawo la mphamvu yokoka pa x-axis

w_y = gawo la mphamvu yokoka pa y-axis

F = mphamvu yokhazikika yopingasa

F_x = gawo la mphamvu pa x-axis

F_y = gawo la mphamvu pa y-axis

N = mphamvu yachibadwa

f_k = mphamvu ya kukangana kwa kinetic

w = mg = 5 (10) = 50 N

w_x = w sin θ = 50 (3/5) = 30 N

w_y = w cos θ = 50 (4/5) = 40 N

F = 50N

F_x = F cos θ = 50 (4/5) = 40 N

F_y = F sin θ = 50 (3/5) = 30 N

N = w_y +F_y = 40 + 30 = 70 N

f_k = μ_k N = 0,2 (70) = 14 N

Gwiritsani ntchito lamulo lachiwiri la Newton:

ΣF = ma

F_x - w_x - f_k = ma

40-30-14 = 5 a

-4 = 5 a

a = -4/5 m/s²

Gwiritsani ntchito fomula ya GLBB kuti muwerengere mtunda womwe chipikacho chimayenda musanayime.

Ndizodziwika kuti:

Liwiro loyambirira (v)_o) = 4 m/s

Kuchepa kwa mphamvu ya flue (a) = -4/5 m/s²

Liwiro lomaliza (v)_t= = 0

Anafunsa kuti: Ulendo wamtunda (maulendo)

Yankho:

v_t² =v_o² + ma axle awiri

0 = 4² + 2 (-4/5) s

0 = 16 – 8/5 s

16 = 8/5 s

16 (5) = masekondi 8

80 = masekondi 8

s = 80/8

s = mamita 10

Yankho lolondola ndi A.

2. Chipika chimayenda kuchokera pamalo opumulira kupita pansi patali. Gawo loyamba la kutsika ndi losalala, ndipo gawo lotsatira pansi ndi lolimba. Pambuyo poyenda kwakanthawi pa gawo lolimba, chipikacho chimayima. Pachifukwa ichi…

(1) ntchito yonse pa boloko si yofanana ndi zero

(2) ntchito yochitidwa ndi mphamvu yokoka ili ndi phindu labwino

(3) ntchito yochitidwa ndi mphamvu yokoka ndi yofanana ndi kusintha kwa mphamvu yomwe ingatheke ya chipikacho

(4) ntchito yochitidwa ndi mphamvu yokangana si yofanana ndi zero

Zokambirana

Pali mphamvu ziwiri zomwe zimagwira ntchito pa chinthu, zomwe ndi mphamvu yokoka ndi kukangana.

Chinthu chikadutsa pamwamba pa malo otsetsereka bwino, mphamvu yokoka yokha ndi imene imagwira ntchito pa chinthucho. Chinthu chikadutsa pamwamba pa malo otsetsereka, kuwonjezera pa mphamvu yokoka, pamakhalanso mphamvu yokoka yomwe imagwira ntchito pa chinthucho.

1. Ntchito yonse pa boloko si yofanana ndi zero.

Ngati ntchito yonse ndi zero, ndiye kuti palibe kusuntha. Bloko imakumana ndi kusuntha, kotero ntchito yonse si zero.

Chiganizo 1 ndi chowonadi

2. Ntchito yochitidwa ndi mphamvu yokoka ili ndi phindu labwino

Ntchito yochitidwa ndi mphamvu yokoka ndi yabwino chifukwa njira ya mphamvu yokoka (yopita pansi) ndi yofanana ndi njira yosunthira chinthucho (yopita pansi).

Chiganizo 2 ndi chowonadi

3. Ntchito yochitidwa ndi mphamvu yokoka ndi yofanana ndi kusintha kwa mphamvu yokoka ya chipikacho, pamenepa ntchito yabwino yochitidwa ndi mphamvu yokoka imapangitsa kuti mphamvu yokoka ya chipikacho ichepe.

Chiganizo 3 ndi chowonadi

4. Ntchito yochitidwa ndi kukangana si zero chifukwa chinthucho chimakumana ndi kusuntha ndipo pali mphamvu yokangana yomwe imagwira ntchito panthawi yosuntha.

Chiganizo 4 ndi chowonadi

Kuyenda molunjika bwino

3. Chidutswa chotsetsereka pansi pa malo otsetsereka opanda kukangana chidzathamanga nthawi zonse.

Chifukwa

Ngati palibe kukangana, kuthamanga kwa chinthu kumakhala kofanana ndi kuthamanga chifukwa cha mphamvu yokoka.

Zokambirana

Ngati palibe kukangana, kyubiki imatsika pansi ndi kufulumira kosalekeza. Mu kugwa kwaulere, chinthu chimagwa ndi kufulumira g, komwe g ndi kufulumira chifukwa cha mphamvu yokoka.

Pakadali pano, pamalo opendekeka, chinthu chimatsika ndi acceleration gx, komwe mtengo wa gx ndi wocheperako kuposa acceleration chifukwa cha mphamvu yokoka. Mtengo wa gx umadaliranso kukula kwa ngodya ya inclination.

Magwero a mafunso

Mafunso a SBMPTN a Fizikiki