Kufamba kwese kwese - matambudziko nemhinduro
Torque
1. Danda rine urefu hwe 140 cm. Pane masimba matatu anoshandiswa padanda, F 1 = 20 N, F 2 = 10 N, uye F 3 = 40 N ine gwara nenzvimbo sezvakaratidzwa mumufananidzo uri pazasi. Chii chinonzi torque chinoita kuti danda ritenderere pakati pehukuru hwedanda?
Zvinozivikanwa:
Pakati pehukuru pacho panowanikwa pakati pedanda.
Kureba kwedanda (l) = 140 cm = 1.4 metres
Simba 1 (F 1 ) = 20 N, ruoko rwechitsigiro 1 (l 1 ) = 70 cm = 0.7 metres
Simba 2 (F 2 ) = 10 N, ruoko rwechibato 2 (l 2 ) = 100 cm – 70 cm = 30 cm = 0.3 mamita
Simba 3 (F 3 ) = 40 N, ruoko rwechitsigiro 3 (l 3 ) = 70 cm = 0.7 metres
Zvinodiwa: Hukuru hwetorque
Solution:
Torque 1 inotenderera mwenje uchitenderera wachi, saka torque 1 inopa chiratidzo chekusashanda zvakanaka.
τ 1 = F 1 l 1 = (20 N)(0.7 m) = -14 N m
Torque 2 inotenderera danda richipesana newachi, saka ichipa chiratidzo chakanaka kutorque 2.
τ 2 = F 2 l 2 = (10 N)(0.3 m) = 3 N m
Torque 3 inotenderera mwenje uchitenderera wachi, saka torque 3 inopa chiratidzo chakanaka.
τ 3 = F 3 l3 = (40 N)(0.7 m) = -28 N m
Torque yemagetsi:
Στ = -14 Nm + 3 Nm – 28 Nm = – 42 Nm + 3 Nm = -39 Nm
Hukuru hwetorque ndeye 39 N m. Nzira yekutenderera kwedanda inoenderana newachi, saka chiratidzo chekusagadzikana chakapihwa.
2. Chii chinonzi net torque inoshanda padanda. Akisi yekutenderera panzvimbo D. (sin 53 o = 0.8)
Zvinozivikanwa:
Kutenderera kwechikamu cheD
F 1 = 10 N uye l 1 = r 1 chivi θ = (40 cm)(chivi 53 o ) = (0.4 m)(0.8) = 0.32 mamita
F 2 = 10√2 N uye l 2 = r 2 chivi θ = (20 cm)(chivi 45 o ) = (0.2 m)(0.5√2) = 0.1√2 mamita
F 3 = 20 N uye l 3 = r 1 chivi θ = (10 cm)(chivi 90 o ) = (0.1 m)(1) = 0.1 mamita
Zvinodiwa: Torque yemagetsi
Solution:
τ 1 = F 1 l 1 = (10 N) (0.32 m) = 3.2 Nm
(Torque 1 inotenderera danda rinopesana newachi saka tinoisa chiratidzo chakanaka kutorque 1)
τ 2 = F 2 l 2 = (10√2 N)( 0.1√2 m) = -2 Nm
(Torque 2 inotenderera mwenje uchitenderera wachi saka tinoisa chiratidzo chekusashanda zvakanaka kutorque 2)
τ 3 = F 2 l 2 = (20 N) (0.1 m) = 2 Nm
(Torque 3 inotenderera danda rinopesana newachi saka tinoisa chiratidzo chakanaka kutorque 3)
Torque yemagetsi:
Στ = τ 1 – τ 1 + τ 3
Στ = 3.2 Nm – 2 Nm + 2 Nm
Στ = 3.2 Nm
3. Chii chinonzi net torque kana axis yekutenderera panzvimbo D. (sin 53 o = 0.8)
Zvinozivikanwa:
Kutenderera kwechikamu chepakati pechinhu D.
Daro riri pakati peF 1 ne axis yekutenderera (r AD ) = 40 cm = 0.4 m
Daro riri pakati peF 2 ne axis yekutenderera (r BD ) = 20 cm = 0.2 m
Daro riri pakati peF 3 ne axis yekutenderera (r CD ) = 10 cm = 0.1 m
F 1 = 10 Newton
F 2 = 10√2 Newton
F 3 = 20 Newton
Chivi 53 o = 0.8
Zvinodiwa: Torque yemagetsi
Solution:
Nguva yesimba 1
Στ 1 = (F 1 )(r AD chivi 53 o ) = (10 N)(0.4 m)(0.8) = 3.2 Nm
(Torque 1 inotenderera danda rinopesana newachi saka tinoisa chiratidzo chakanaka kutorque 1)
Nguva yesimba 2
Στ 2 = (F 2 )(r BD chivi 45 o ) = (10√2 N)(0.2 m)(0.5√2) = -2 Nm
(Torque 2 inotenderera mwenje uchitenderera wachi saka tinoisa chiratidzo chekusashanda zvakanaka kutorque 2)
Nguva yesimba 3
Στ 3 = (F 3 )(r CD chivi 90 o ) = (20 N)(0.1 m)(1) = 2 Nm
(Torque 2 inotenderera danda rinopesana newachi saka tinoisa chiratidzo chakanaka kutorque 3)
Torque yemagetsi:
Στ = Στ 1 + Στ 2 + Στ 3
Στ = 3.2 – 2 + 2
Στ = 3.2 mamita eNewton
Nguva yekusagadzikana
4. Kureba kwewaya = 12 m, l 1 = 4 m. Usatarise huremu hwewaya. Ndeipi nguva yekusashanda kwehurongwa.
Zvinozivikanwa:
Huremu hweA (mA ) = 0.2 kg
Huremu hweB (m B ) = 0.6 kg
Daro riri pakati peA ne axis yekutenderera (r A ) = mamita mana
Daro riri pakati peB ne axis yekutenderera (r B ) = 12 – 4 = 8 metres
Zvinodiwa: Nguva yekusashanda zvakanaka kwehurongwa
Solution:
Nguva yekusagadzikana kweA
I A = (m A )(r A 2 ) = (0.2)(4) 2 = (0.2)(16) = 3.2 kg m2
Nguva yekusagadzikana kweB
I B = (m B )(r B 2 ) = (0.6)(8) 2 = (0.6)(64) = 38.4 kg m 2
Nguva yekusagadzikana kwehurongwa:
I = I A + I B = 3.2 + 38.4 = 41.6 kg m 2
5. Simba re6-N rinoiswa patambo yakaputirwa nepulley ine huremu hweM = 5 kg uye radius R = 20 cm. Chii chinonzi angular acceleration yepulley. Pulley iyi isimbi yakasimba yakafanana.
Zvinozivikanwa:
Simba (F) = 6 Newton
Huremu (M) = 5 kg
Nharaunda (R) = 20 cm = 20/100 m = 0.2 m
Zvinodiwa: Kukurumidza kwekona (α)
Solution:
Nguva yesimba:
τ = FR = (6 Newton)(0.2 metres) = 1.2 N m
Nguva yekusashanda zvakanaka kwe silinda yakasimba:
Ini = 1/2 MR 2
I = 1/2 (5 kg)(0.2 m) 2
I = 1/2 (5 kg)(0.04 m2 )
Ini = 1/2 (0.2)
I = 0.1 kg m 2.
Kukurumidza kwekona:
τ = ini α
α = τ / I = 1.2 / 0.1 = 12 rad s -2
6. Bhokisi rehuremu = 4 kg rakarembera kubva patambo rakatenderedzwa nepulley yehuremu = 8 kg uye radius R = 10 cm. Kukurumidza kunokonzerwa negiravhiti ndeye 10 ms -2 . Chii chinonzi linear acceleration yebhokisi? Pulley iyi isimbi yakasimba yakafanana.
Zvinozivikanwa:
Huremu hwepulley (m) = 8 kg
Nharaunda yepulley (r) = 10 cm = 0.1 m
Huremu hwebhuroko (m) = 4 kg
Kukurumidza kunokonzerwa negiravhiti (g) = 10 m/s 2
Huremu (w) = mg = (4 kg)(10 m/s 2 ) = 40 kg m/s 2 = 40 Newtons
Zvinodiwa: Kukurumidza kuwa kwebhuroko
Solution:
Nguva yekusashanda kwe silinda yakasimba:
I = 1/2 MR 2 = 1/2 (8 kg)(0.1 m) 2 = (4 kg)(0.01 m 2 ) = 0.04 kg m 2
Nguva yesimba:
τ = F r = (40 N) (0.1 m) = 4 Nm
Kukurumidza kwekona:
Στ = I α
4 = 0.04 α
α = 4 / 0.04 = 100
Kukurumidza kwemutsara:
a = r α = (0.1)(100) = 10 m/s 2
7. Bhokisi rine huremu hwe m rakarembera kubva patambo yakaputirwa papulley. Kana kukurumidza kwebhokisi kuri am/s 2 , chii chinoitika panguva yekusashanda kwepulley.
Zvinozivikanwa:
huremu = w = mg
Ruoko rwechirevheta = R
Kukurumidza kwekona = α
Kukurumidza kwekuwa kwebhuroko = a ms -2
Zvinodiwa: Nguva yekusashanda zvakanaka kwepulley (I)
Solution:
Kubatana kuripo pakati pekuwedzera simba uye kuwedzera simba kwe angular:
a = R α
α = a / R
Nguva yekusaita basa:
τ = ini α
I = τ : α = τ : a / R = τ (R / a) = τ R a -1
Mwero wekona
8. Chidimbu che 0.2-gram chinofamba mudenderedzwa nekumhanya kwakafanana kwe 10 m/s. Radius yedenderedzwa iri 3 cm. Chii chinonzi angular momentum yechinhu ichi?
Zvinozivikanwa:
Huremu hwechidimbu (m) = 0.2 gram = 2 x 10 -4 kg
Kumhanya kwekona (ω) = 10 rad s -1
Nharaunda (r) = 3 cm = 3 x 10 -2 mamita
Zvinodiwa: Kufamba kwekona kwechikamu
Solution:
Kuenzanisa kwe angular momentum:
L = I ω
I = angular momentum, I = nguva yekusaita basa, ω = angular speed
Nguva yekusagadzikana (kwezvimedu):
Ini = mr 2 = (2 x 10 -4 )(3 x 10 -2 ) 2 = (2 x 10 -4 )(9 x 10 -4 ) = 18 x 10 -8
Mwenje wekona:
L = I ω = (18 x 10 -8 )(10 rad s -1 ) = 18 x 10 -7 kg m 2 s -1
- Chii chinonzi kufamba kwese kwese kwese?
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- mhinduro: Simba rekinetic rinotenderera isimba rinokonzerwa nekutenderera kwechinhu chakatenderedza axis. Rinopihwa nefomura: , apo inguva yekusagadzikana uye ndiyo kasi yekona.