3 cov lus nug txog kev sib npaug ntawm qhov ceev ntawm lub kaum sab xis
1. Ib yam khoom uas txav mus los hauv txoj kev voj voog muaj lub vojvoog ntawm 0.5 m. Lub khoom me me no muaj peev xwm npog lub kaum sab xis ntawm 60π rad hauv 15 vib nas this. Txheeb xyuas qhov ceev ntawm lub kaum sab xis ntawm yam khoom.
Paub:
Lub vojvoog (r) = 0.5 meters
Lub kaum sab xis (θ) = 60π rad
Lub sijhawm luv (t) = 15 vib nas this
Xav tau: angular velocity (ω)
tshuaj:
θ = ω t
60π = ω (15)
ω = 60π / 15 = 4π rad/s
2. Lub log tsheb kauj vab uas muaj lub vojvoog ntawm 30 cm tig ntawm qhov ceev tas li. Lub qhov cua ntawm lub log tsheb tuaj yeem tig ntawm lub kaum sab xis ntawm 120π rad rau 10 vib nas this. Txheeb xyuas qhov ceev ntawm lub kaum sab xis.
Paub:
Lub vojvoog (r) = 30 cm
Lub kaum sab xis (θ) = 120π rad
Lub sijhawm luv (t) = 10 vib nas this
Xav tau: angular velocity (ω)
tshuaj:
θ = ω t
120π = ω (10)
ω = 120π / 10 = 12π rad/s
3. Txoj hlua khi ib ncig ntawm lub log uas muaj lub vojvoog R = 25 cm raws li qhia. Yog tias ib qho ntawm txoj hlua (qhov chaw A) muaj qhov ceev ntawm 5 m/s ces qhov ceev ntawm lub log tig yog...
Paub:
Lub vojvoog (r) = 25 cm = 0.25 meters
Ceev (v) = 5 m/s
Xav tau: angular velocity (ω)
tshuaj:
Cov mis rau kev sib raug zoo ntawm qhov ceev ntawm lub kaum sab xis, qhov ceev ntawm kab ncaj thiab lub vojvoog:
v = r ω
5 = (0,25) ω
ω = 5 / 0,25 = 20 rad/s
