Mehlala e 5 ea lipotso tsa matla a kinetic a potolohang
1. Ntho e na le motsotso wa ho se inertia wa 1 kg m2 o potolohang hodima axis e tsitsitseng ka lebelo la angular la 2 rad/s. Matla a kinetic a potolohang a ntho ke afe ?
Puisano
Hoa tsebahala hore:
Motsotso oa ho se inertia (I) = 1 kg m2
Lebelo la Angular (ω) = 2 rad/s
O botsitse: Matla a kinetic a potolohang (EK)
Karabo:
Foromo ea matla a kinetic a potolohang:
EK = 1/2 I ω2
Tlhaloso: EK = matla a kinetic a potolohang (kg m)2/s2), I = motsotso oa ho se inertia (kg m2), ω = lebelo la angular (rad/s)
Matla a kinetic a potolohang:
EK = 1/2 I ω2 = 1/2 (1)(2)2 = 1/2 (1)(4) = 2 Joule
2. Pulley e tiileng ea disc e na le boima ba 20 kg le radius ea limithara tse 0,2. Haeba pulley e potoloha moleng oa eona ka lebelo le sa fetoheng la 4 rad/motsotsoana, matla a kinetic a potolohang a pulley ke afe?
Puisano
Hoa tsebahala hore:
Boima ba pulley ea disc e tiileng (m) = 20 lik'hilograma
Radius ea pulley ea disc e tiileng (r) = limithara tse 0,2
Lebelo la Angular (ω) = 4 radians/motsotsoana
O botsitse: Matla a kinetic a potolohang a pulley ke afe?
Karabo:
Foromo ea motsotso oa inertia oa disc e tiileng haeba e potoloha holima axis joalo ka ha ho bontšitsoe setšoantšong:
Ke = halofo ea monghali2
Tlhaloso: I = motsotso oa ho se inertia (kg m)2), m = boima (kg), r = radius (limithara)
Nako ea ho se sebetse hantle ha diski e tiileng:
Ke = 1/2 (20)(0,2)2 = (10)(0,04) = 0,4 kg m2
Matla a kinetic a potolohang a pulley:
EK = 1/2 I ω2 = 1/2 (0,4)(4)2 = (0,2)(16) = 3,2 Li-joule
3. Bolo e tiileng e boima ba 10 kg le radius ea limithara tse 0,1 e potoloha ho potoloha axis ea eona ka lebelo la angular la 10 rad/s. Fumana matla a kinetic a potolohang a bolo e tiileng!
Puisano
Hoa tsebahala hore:
Boima ba bolo e tiileng (m) = 10 kg
Radius ea selika se tiileng (r) = limithara tse 0,1
Lebelo la Angular (ω) = 10 radians/motsotsoana
O botsitse: Matla a kinetic robehilebolo e tiileng
Karabo:
Foromo ea motsotso oa inertia oa bolo e tiileng haeba e potoloha holima axis joalo ka ha ho bontšitsoe setšoantšong:
Ke = (2/5) monghadi2
Tlhaloso: I = motsotso oa ho se inertia (kg m)2), m = boima (kg), r = radius (limithara)
Motsotso oa ho se tsitse ha selika se tiileng:
Ke = (2/5)(10)(0,1)2 = (4)(0,01) = 0,04 kg m2
Matla a kinetic a potolohang a selika se tiileng:
EK = 1/2 I ω2 = 1/2 (0,04)(10)2 = (0,02)(100) = 2 Li-joule
4. Karoloana e boima ba lik'hilograma tse 0,5 e tsamaea ka selikalikoe ka lebelo le sa fetoheng la 2 rad/s. Fumana matla a kinetic a potolohang a karoloana haeba radius ea tsela ea karoloana e le 10 cm.
Puisano
Hoa tsebahala hore:
Boima ba karoloana (m) = 0,5 kg
Radius ea selika-likoe se tiileng (r) = 10 cm = 10/100 = 0,1 metres
Lebelo la Angular (ω) = 2 radians/motsotsoana
O botsitse: Matla a kinetic a potolohang a likaroloana
Karabo:
Foromo ea motsotso oa inertia ea karoloana:
Ke = Monghali.2 = (0,5)(0,1)2 = (0,5)(0,01) = 0,005 kg m2
Matla a kinetic a potolohang a likaroloana:
EK = 1/2 I ω2 = 1/2 (0,005)(2)2 = 1/2 (0,005)(4) = (0,005)(2) = 0,01 Joule
5. Disiki e tiileng e nang le sebopeho se ts'oanang e qala ho potoloha moleng oa eona ka lebelo la angular la 4 rad/s. Boima le radius ea disk ke 1 kg le 0,5 m. Haeba lesale le nang le boima ba 0,2 kg le radius ea 0,1 m le behiloe holim'a disk, moo setsi sa lesale se leng ka holimo ho setsi sa disc, disc le lesale li tla potoloha hammoho ka matla a potolohang a kinetic a…
Puisano
Hoa tsebahala hore:
Boima ba silindara e tiileng (m1) = 1 lik'hilograma
Radius ea silindara e tiileng (r)1) = limithara tse 0,5
Lebelo le potolohang la silindara e tiileng (ω1) = 4 rad/s
Boima ba lesale (m2) = 0,2 lik'hilograma
Radiyo ya lesale (r)2) = limithara tse 0,1
O botsitse: Matla a kinetic a potolohang a silindara le lesale
Karabo:
Pele bala lebelo la angular la silindara le lesale:
Nako ea ho se sebetse hantle ha silindara e tiileng: I = 1⁄2 m1 r12 = 1⁄2 (1)(0,5)2 = (0,5)(0,25) = 0,125 kg m2
Motsotso oa ho se tsitse ha lesale: Ke = monghali2 = (0,2)(0,1)2 = (0,2)(0,01) = 0,002 kg m2
Nako ea ho se sebetse ha silindara e tiileng le lesale (I) = 0,125 + 0,002 = 0,127 kg m2
Motsamao o potolohang qalo (L1) = Momentum oa ho qetela oa angular (L2)
I1 ω1 = KE2 ω2
(0,125) (4) = (0,125 + 0,002)(ω2)
(0,5) = (0,127)(ω2)
ω2 = 0,5 : 0,127
ω2 = 4 rad/s
Bala matla a kinetic a potolohang a silindara le selikalikoe:
EK = 1/2 I ω2 = 1/2 (0,127)(4)2 = (0,127)(8) = 1,016 Li-joule
