Fomula Yogwira Ntchito ndi Chiphunzitso cha Mphamvu ya Kinetic

Zitsanzo za mafunso ndi ma formula a ntchito ndi chiphunzitso cha mphamvu ya ntchito-kinetic

Bizinesi

1. Mdzukulu akukankhira mpando wa agogo ake pa njinga ya olumala m'paki yozungulira ndi mphamvu ya 20 N, utali wa pakiyo ndi mamita 7, kodi mdzukuluyo amagwira ntchito yochuluka bwanji pozungulira kawiri?

1. 0 ma joule
2. 1400 ma joule
3. 1540 ma joule
4. 1760 ma joule

Zokambirana
Fomula ya Bizinesi: Ntchito = Mphamvu x Kusamutsidwa
Ngati mdzukulu akankhira mpando wa olumala kawiri, mdzukulu ndi mpando wa olumala onse adzabwerera pamalo awo oyamba. Popeza kubwerera pamalo awo oyamba ndi zero, kusamuka kwawo ndi zero.
Kotero khama lomwe mdzukuluyo wapanga ndi zero.
Yankho lolondola ndi A.

2. Wosamalira kabati akukankhira kabati pansi ndi mphamvu ya 350 N. Pansi pake pali mphamvu yokangana ya 70 N. Ntchito yosuntha kabati mamita 6 ndi iyi:

1. 45 y
2. 72 y
3. 1680 y
4. 2580 y

Zokambirana
Amadziwika kuti:
Mphamvu yokakamiza (F) = 350 Newton
Mphamvu yokangana (F)_gwedezani) = 70 Newton
Kusamutsa kabati (ma) = mamita 6
Anafunsa kuti: Bizinesi (W)
Yankho:
Pali mphamvu ziwiri zomwe zimagwira ntchito pa chinthu, zomwe ndi mphamvu yokankhira (F) ndi mphamvu yokangana (F)._gwedezani).
Mphamvu yokankhira ili mbali imodzi ndi kusuntha kwa kabati, kotero mphamvu yokankhira imagwira ntchito yabwino. Mosiyana ndi zimenezi, mphamvu yokankhira ili mbali yosiyana ndi kusuntha kwa kabati, kotero mphamvu yokankhira imagwira ntchito yoipa.
Ntchito yochitidwa ndi gulu lotsogolera:
W = F s = (350 Newton)(mamita 6) = 2100 Newton mamita = 2100 Joules
Ntchito yochitidwa ndi mphamvu yokangana:
W = – (F_gwedezani)(s) = – (70 Newton)(mamita 6) = – 420 Newton mamita = – 420 Joules
Khama lonse:
Chiwerengero chonse = 2100 Joules – 420 Joules
Chiwerengero chonse cha W = 1680 Joule
Yankho lolondola ndi C.

Chiphunzitso cha mphamvu ya kinetic yogwira ntchito

3. Mphamvu yosasinthika ya 8 N imagwira ntchito pa chinthu cholemera makilogalamu 16. Ngati chinthucho chili pamalo opumulirako poyamba, ndiye kuti liwiro la chinthucho pambuyo pa mphamvuyo kwa masekondi anayi ndi….

1. 0,5 m / s
2. 2 m / s
3. 4 m / s
4. 8 m / s

Zokambirana
Amadziwika kuti:
Mphamvu yosalekeza (F) = 8 Newton
Kulemera kwa chinthu (m) = 16 kg
Liwiro loyambirira la chinthucho (v)_o) = 0 m/s
Nthawi yomwe mphamvu imagwira ntchito pa chinthu (t) = masekondi 4
Anafunsa kuti: Liwiro lomaliza la chinthucho (v)_t)
Yankho:
Ntchito = Kusintha kwa mphamvu ya kinetic
W = EK yomaliza – EK yoyambirira
W = ½ mv_t² – ½ mv_o²
W = ½ mv_t² - 0
W = ½ mv_t² —— Chiyerekezo 1

Ntchito = Mphamvu x Kusamutsidwa
W = F s
W = masekondi 8
Gwiritsani ntchito fomula ya GLBB kuti muwerengere kusuntha (s)
s = v_o t + ½ pa²
Kufotokozera: s = kusamuka, v_o = liwiro loyambirira, t = nthawi, a = kufulumira
s = 0 + ½ pa² = ½ pa² —-> a = (v_t -v_o) / t = v_t
s = ½ (v_t / t) t²
s = ½ (v_t) t
Sinthani ma displacement (s) mu equation ya ntchito ndi ma displacement (s) mu equation iyi:
W = masekondi 8
W = 8(1/2)(v_t(t)
W = (4)(v_t)(t) —— Chiyerekezo 2

Chiyerekezo 1 = Chiyerekezo 2
W = W
½ mv_t² = (4)(v_t(t)
½ mv_t = (4)(t)
½ (16)(v)_t) = 4(4)
8 v_t = 16
v_t = 16/8
v_t = mamita awiri/sekondi
Yankho lolondola ndi B.

4. Kuonjezera liwiro la chinthu kufika pa liwiro loyambirira kawiri, khama la...

1. Mphamvu yake yoyambira ya kinetic imaposa katatu
2. Mphamvu yake yoyambira ya kinetic imaposa katatu
3. Mphamvu yake yoyambira ya kinetic imaposa katatu
4. Mphamvu yake yoyambira ya kinetic imaposa katatu

Zokambirana
Amadziwika kuti:
Tiyerekeze kuti kulemera kwa chinthucho (m) = 1 kg
Tiyerekeze kuti liwiro loyamba (v)_o) = 1 m/s
Liwiro lomaliza (v)_t) = 2 x liwiro loyambirira = 2 x 1 = 2 m/s
Anafunsa kuti: Khama = … ?
Yankho:
Mphamvu yoyambirira ya kinetic:
EK yoyambirira = ½ mv_o² = ½ (1)(1)² = ½ (1)(1) = ½ (1) = 0,5
Mphamvu yomaliza ya kinetic pamene liwiro la chinthucho lili kawiri liwiro lake loyambirira:
EK Yomaliza = ½ mv_t² = ½ (1)(2)² = ½ (4) = 2

Chiphunzitso cha mphamvu ya kinetic yogwira ntchito:
Ntchito = Kusintha kwa mphamvu ya kinetic
Ntchito = Mphamvu yomaliza ya kinetic - Mphamvu yoyambirira ya kinetic
Khama = 2 – 0,5
Khama = 1,5

Mphamvu yoyambirira ya kinetic = 0,5
Khama = 3 x 0,5 = 1,5
Kotero kuti muwonjezere liwiro la chinthu kufika pa liwiro lake loyambirira kawiri kumafuna ntchito yambiri. Mphamvu yake yoyambira ya kinetic imaposa katatu.
Yankho lolondola ndi B.

Gwero la funso:

Mafunso a OSN a Sukulu ya Sekondale ya Fiziki ya Sukulu ya Sekondale