Mafunso a Chitsanzo cha Mphamvu ya Pakati

Zitsanzo 4 za Mafunso a Centripetal Force

1. Chinthu cholemera magalamu 200 chimamangiriridwa ku chingwe chopepuka kenako n’kuzunguliridwa mopingasa ndi liwiro la angular imakhalabe pa 5 rad s^-1, monga momwe zilili pachithunzichi. Ngati kutalika kwa chingwe ndi l = 60 cm, ndiye kuti kukula kwa mphamvu yapakati yomwe ikugwira ntchito pa chinthucho ndi...

A. 0,3 N

B. 0,6 N

C. 3 N

D. 6 N

E. 30 N

Zokambirana

Amadziwika kuti:

Kulemera kwa chinthu (m) = magalamu 200 = 200/1000 kg = 2/10 kg = 0,2 kg

Liwiro la angular (ω) = ma radians awiri/sekondi

Kutalika kwa chingwe = radius (r) ya njira yozungulira = 60 cm = 60/100 mamita = 0,6 mamita

Anafunsa kuti: Mphamvu yapakati yomwe imagwira ntchito pa chinthu ndi yaikulu kwambiri.

Yankho:

Mphamvu yapakati ndi mphamvu yomwe imayambitsa chinthu kuti chiziyenda mofulumira pakati. Fomula ya mphamvu yapakati ndi iyi:

∑F = ma_s

∑F = mv²/r = m ω² r

Zambiri: ∑F = mphamvu yapakati, m = kulemera kwa chinthu, v = liwiro la tangential, ω = liwiro la angular, r = radius ya njira yozungulira.

∑F = m ω² r = (0,2)(5)² (0,6) = (0,2)(25)(0,6) = 3 Newtons

Yankho lolondola ndi C.

2. Wophunzira akupotoza mwala womangiriridwa kumapeto kwa chingwe. Mwalawo umazunguliridwa mopingasa monga momwe tawonetsera pamwambapa. Ngati liwiro la kuzungulira kwa mwala lawirikiza kawiri, mphamvu yapakati imakhala...

A. Yoyambirira kasanu ndi kamodzi

B. yoyambirira kasanu

C. yoyambirira nthawi 4

D. kawiri kachiwiri

E. Yoyamba kawiri

Zokambirana

Amadziwika kuti:

Unyinji wa mwala = m

Liwiro la mwala = v

Kutalika kwa chingwe = radius = r

Anafunsa kuti: Ngati liwiro lawirikiza kawiri, mphamvu yapakati imakhala…

Yankho:

Ngati liwiro lawirikiza kawiri, ndiye kuti mphamvu yapakati imakhala:

Mphamvu yapakati imakhala yowirikiza kanayi kuposa yoyamba.

Yankho lolondola ndi C.

3. Mzere wokhota pamsewu wathyathyathya wapangidwa kuti galimoto iziyenda pa liwiro lapamwamba la 10 m/s.^-1. Amadziwika kuti coefficient of friction pakati pa tayala ndi msewu ndi 0,5 ndipo radius of curvature ya msewu ndi R m. Kenako mtengo wa R ndi…. (g = 10 ms^-2)

A. mamita 7,5

B. mamita 8,0

C. 10 mamita

D. 15 mamita

E. mamita 20

Zokambirana

Amadziwika kuti:

Liwiro (v) = 10 m/s

Kuchuluka kwa kukangana pakati pa tayala ndi msewu (μ_s= = 0,5

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

Anafunsa kuti: Ma radius a kupindika kwa msewu (R mita)

Yankho:

Mphamvu yokhayo yomwe imachokera mbali yopingasa imagwira ntchito pa galimoto ikatembenuka ndi mphamvu yokangana yosasinthasinthaFomula ya mphamvu yokangana yosasinthasintha:

4. Galimoto ikuyendetsa mokhota pamsewu pamalo a M monga momwe chithunzi chili pansipa chikusonyezera.

Kuchuluka kwa kukangana kosasinthasintha pakati pa gudumu ndi msewu ndi 0,4 (kuthamanga kwa mphamvu yokoka 10 ms).^-2). Kuti galimoto isatuluke panjira, liwiro lalikulu lomwe limaloledwa ndi…

A. √10 ms^-1

B. 2√10 ms^-1

C. 4√10 ms^-1

D. 5√10 ms^-1

6√10 ms^-1

Zokambirana

Amadziwika kuti:

Chokwanira cha kukangana kosasinthasintha (μ)_s= = 0,4

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

Ulalo wozungulira (R) = mamita 40

Anafunsa kuti: liwiro lalikulu (v)

Yankho:

Fomula Lamulo lachiwiri la Newton pada kuyenda kozungulira kofanana

Zambiri:

ΣF = mphamvu yapakati = mphamvu yochokera = mphamvu yonse, m = kulemera kwa chinthu, a_s = kuthamanga kwapakati, v = liwiro lolunjika, R = utali wozungulira wa kupindika

Mphamvu yapakati

Mphamvu yapakati ndi mphamvu yochokera pakati pa njira yozungulira. Galimoto ikayenda mozungulira, mphamvu yokhayo yolunjika pakati ndi kukangana kosasinthasintha, kotero kukangana kosasinthasintha ndi mphamvu yapakati.

Fomula ya mphamvu yokangana yosasinthasintha:

Zambiri:

μ_s = coefficient of static friction, w = kulemera kwa chinthu, m = kulemera kwa chinthu, g = kuthamanga chifukwa cha mphamvu yokoka.

Werengani liwiro lalikulu (v):

Yankho lolondola ndi C.

Gwero la funso:

Mafunso a National Examination Physics a Senior High School/Vocational High School