Mibvunzo mitatu pamusoro peFriction force equation
1. Bhokisi A 3 kg inoiswa patafura yobva yasungirirwa patambo yakabatana nedombo B = 2 kg kuburikidza nepulley sezvakaratidzwa. Huremu nekukweshana kwemapulley zvinoregeredzwa. Kukurumidzisa nekuda kwegiravhiti g = 10 m/s 2 . Sarudza kukurumidza kwesystem uye kumanikidzwa kwetambo kana:
a) tafura yakatsetseka
b) tafura isina kurongeka ine chiyero chekukweshana kwekinetic che 0.4
Anozivikanwa:
Huremu hwebhuroko A (m A ) = 3 kg
Huremu hwedombo B (m B ) = 2 kg
Kukurumidza kunokonzerwa negiravhiti (g) = 10 m/s 2
Kurema kwebhuroko A (w A ) = mg = (3)(10) = 30 Newtons
Kurema kwedombo B (w B ) = mg = (2)(10) = 20 Newtons
Zvinodiwa: Kukurumidza kwehurongwa (a) uye kushushikana kwetambo (T)
Solution:
a) tafura yakatsetseka
Verenga kukurumidza kwehurongwa uchishandisa fomura yemutemo wechipiri waNewton:
ΣF = ma
w B = (m A + m B ) a
20 = (3 + 2) a
20 = 5 a
a = 20 / 5 = 4 m/s 2
Verenga kumanikidzwa kwetambo uchishandisa fomura yekumanikidzwa kwetambo:
Kushushikana kwetambo pabhuroko A:
ΣF = m A a
T = m A a = (3)(4) = 12 Newtons
Kumanikidzwa kwetambo pabhuroko B:
ΣF = m B a
w B – T = (2)(4)
20 – T = 8
T = 20 – 8 = 12 Newton
b) tafura isina kurongeka ine chiyero chekukweshana kwekinetic che 0.4
Simba rekukweshana kwekinetic:
F k = µ k N = (0,4)(30) = 12 Newtons
Verenga kukurumidza kwehurongwa uchishandisa fomura yemutemo wechipiri waNewton:
ΣF = ma
w B – f k = (m A + m B ) a
20 – 12 = (3 + 2) a
8 = 5 a
a = 8 / 5 = 1,6 m/s 2
Verenga kumanikidzwa kwetambo uchishandisa fomura yekumanikidzwa kwetambo:
Kushushikana kwetambo pabhuroko A:
ΣF = m A a
T – fk = m A a
T – 12 = (3)(1,6)
T – 12 = 4,8
T = 4,8 + 12 = 16,8 Newtons
Kumanikidzwa kwetambo pabhuroko B:
ΣF = m B a
w B – T = (2)(1,6)
20 – T = 3,2
T = 20 – 3,2 = 16,8 Newton
2. Chinhu chine huremu hwe10 kg chiri mudenderedzwa rakatwasuka. Chiyero chekukakavadzana kwakagadzika i0.4 uye chiyero chekukakavadzana kwekinetic i0.35. g = 10 m/s 2. Kana chinhu chikapihwa simba rakatwasuka risingaperi re25 N, hukuru hwesimba rekukakavadzana rinoshanda pachinhu chacho i…
Anozivikanwa:
Huremu hwechinhu (m) = 10 kg
Chiyero cheStatic friction (µ s ) = 0.4
Chiyero chekukweshana kwekinetic (µk) = 0.35
Kukurumidza kunokonzerwa negiravhiti (g) = 10 m/s 2
Simba rakatwasuka (F) = 25 N
Simba rinokwevera zvinhu pasi (w) = mg = (10)(10) = 100 Newtons
Simba rakajairika (N) = w = 100 Newtons
Zvinodiwa: Huwandu hwekukweshana kwesimba (fs ) uye kinetic (f k )
Solution:
Simba rekukakavadzana kwechimiro chisina kusimba::
f s = µ s N = (0,4) (100) = 40 Newtons
Simba reKinetic Friction:
f k = µ k N = (0,35)(100) = 35 Newtons
Simba rakatambanuka rinongova maNewton makumi maviri nemashanu chete saka harikwanise kufambisa zvinhu parizvino.
3. Huremu hwemabhuroko A neB ari mumufananidzo i10 kg ne5 kg zvakateerana. Chiyero chekukweshana pakati pebhuroko A nendege i0.2. Kudzivirira bhuroko A kuti risafambe, huremu hushoma hwebhuroko C hunodiwa ndi…
Anozivikanwa:
Huremu hwebhuroko A (m A ) = 10 kg
Huremu hwebhuroko B (m B ) = 5 kg
Coefficient yekukweshana kwe static block A (µ s ) = 0,2
Kukurumidza kwesimba regiravhiti (g) = 10 m/s 2
Huremu hwebhuroko A (w A ) = m A g = (10)(10) = 100 Newtons
Huremu hwebhuroko B (w B ) = m B g = (5)(10) = 50 Newtons
Kukweshana kwakasimba (fs ) = µs N = (0,2)(w A + w C ) = (0,2)(100 + w C ) = 20 + 0,2 w C
Akabvunzwa: Huremu hwebhuroko C hwekuchengetedza sisitimu iri pakadzikama
Mhinduro:
Sisitimu iyi haina kumira zvakanaka saka fomura yemutemo wekutanga waNewton inoshandiswa:
ΣF = 0
w B – fs = 0
50 – (20 + 0,2 w C ) = 0
50 – 20 – 0,2 w C = 0
30 – 0,2 w C = 0
30 = 0,2 w C
w C = 30 / 0,2 = 300 / 2 = 150 Newtons
Huremu hwebhuroko C = 150 / 10 = 15 Kg
