3 Piv txwv ntawm cov lus nug txog lub ntiajteb txawj nqus
1. Ib yam khoom muaj qhov hnyav 1 kg. Yog tias qhov kev nrawm vim lub ntiajteb txawj nqus = 10 m/s2, qhov khoom ntawd hnyav npaum li cas?
Kev Sib Tham
Nws yog paub :
Qhov hnyav ntawm yam khoom (m) = 1 kg
Kev nrawm vim lub ntiajteb txawj nqus (g) = 10 m/s2
Nug Qhov hnyav ntawm yam khoom (w)
Jawb :
Cov mis ntawm lub ntiajteb txawj nqus:
w = mg
Cov Ntaub Ntawv:
m = pawg (chav thoob ntiaj teb yog kilogram, luv kg)
g = kev nrawm vim lub ntiajteb txawj nqus (cov chav thoob ntiaj teb yog meters ib ob squared, luv m/s2)
w = lub ntiajteb txawj nqus (cov chav thoob ntiaj teb yog kg m/s2 (tseem hu ua Newton)
Qhov hnyav ntawm yam khoom yog:
w = (1 kg)(10 m/s)2) = 10 kg m/s2 = 10 Newtons
2. Saib cov duab (a) thiab (b) hauv qab no.
(a) Kos lub vector gravity ntawm yam khoom, hauv daim duab (a).
(b) Kos lub vector gravity, qhov khoom ntawm lub vector gravity uas sib luag rau lub dav hlau inclined thiab qhov khoom ntawm lub vector gravity perpendicular rau lub dav hlau inclined, hauv daim duab (b)!
Kev Sib Tham
Qhov kev taw qhia ntawm lub ntiajteb txawj nqus (w) yog perpendicular downwards los yog perpendicular rau lub plawv ntawm lub ntiaj teb.
wx = feem kab rov tav ntawm lub ntiajteb txawj nqus thiab wy = feem ntsug ntawm lub ntiajteb txawj nqus.
3. Yog tias qhov hnyav ntawm yam khoom = 1 kg thiab qhov kev nrawm vim yog lub ntiajteb txawj nqus = 10 m/s 2 , txiav txim siab (a) qhov loj ntawm lub zog gravitational (b) qhov loj ntawm cov khoom ntawm lub zog gravitational vector sib luag rau lub dav hlau inclined thiab qhov loj ntawm cov khoom ntawm lub zog gravitational vector perpendicular rau lub dav hlau inclined.
Kev Sib Tham
Lub zog ntawm lub ntiajteb txawj nqus:
w = mg = (1 kg)(10 m/s)2) = 10 kg m/s2 = 10 Newtons
Qhov loj ntawm cov khoom ntawm lub zog gravitational parallel rau lub dav hlau inclined:
wx = w sin 30o = (10 N)(0,5) = 5 Newtons
Qhov loj ntawm cov khoom ntawm lub zog gravitational perpendicular rau lub dav hlau inclined:
Wy = w cos 30o = (10 N)(0,5√3) = 5√3 Newtons
[Lus Askiv: Qhov hnyav thiab qhov hnyav - teeb meem thiab kev daws teeb meem ]
