Cov Khoom Siv Ncaj Qha
Kev txav mus los yog ib qho xwm txheej uas peb pom tas li hauv lub neej txhua hnub. Ib ceg ntawm physics uas kawm txog kev txav mus los hu ua mechanics. Ib ceg ntawm mechanics uas tham txog seb ib yam khoom txav mus li cas, yam tsis xav txog qhov ua rau ntawm kev txav mus los, hu ua kinematics . Ntawm qhov tod tes, ib ceg ntawm mechanics uas tham txog qhov ua rau ntawm kev txav mus los thiab piav qhia vim li cas cov khoom txav mus los raws li lawv ua hu ua dynamics. Hauv cov ncauj lus no, txhua yam khoom txav mus los raug suav hais tias yog ib qho khoom me me lossis ib qho taw tes (.). Cov khoom txav mus los raug suav hais tias yog cov ntsiab lus tsuas yog kom yooj yim rau peb qhov kev tshuaj xyuas. Xav txog yog tias ib qho taw tes txav mus rau hauv ib txoj kab ncaj, ces nws txoj kev taug kev yuav tsim ib txoj kab ncaj.
Ib yam khoom hu ua kev txav mus los ncaj yog tias nws txoj kev ncaj. Yog tias nws txoj kev nkhaus, yam khoom tsis yog kev txav mus los ncaj. Kev txav mus los ntawm ib yam khoom, suav tias yog ib qho khoom me me, yog ib-seem. Kev txav mus los ib-seem tuaj yeem tshwm sim kab rov tav (sib luag rau x-axis) lossis ntsug (sib luag rau y-axis).
Piv txwv txog teeb meem
1. Cov Lus Nug Txog Kev Xeem Hauv Tebchaws Xyoo 2017
Saib daim duab!
Qhov deb tshaj plaws uas ib yam khoom taug kev hauv ib lub sijhawm…
A. 0 txog 10 vib nas this
B. 10 txog 20 vib nas this
C. 20 txog 30 vib nas this
D. 30 txog 50 vib nas this
E. 50 txog 70 xyoo
Kev Sib Tham
Cov qauv nrug deb:
s = vt
Qhov deb = thaj chaw ntxoov ntxoo.
Qhov deb tshaj plaws = thaj chaw loj tshaj plaws.
A. ½ (10-0)(20-0) = ½ (10)(20) = (5)(20) = 100
B. (20-10)(10-0) + (½)(20-10)(20-10) = (10)(10) + ½ (10)(10) = 100 + (5)(10) = 100 + 50 = 150
C. (30-20)(10-0) = (10)(10) = 100
D. (50-30)(10-0) = (20)(10) = 200
E (70-50)(10-0) + ½ (70-50)(30-10) = (20)(10) + ½ (20)(20) = 200 + (10)(20) = 200 + 200 = 400
Cov lus teb yog yog E.
2. Cov Lus Nug Txog Kev Xeem Hauv Tebchaws Xyoo 2017
Ib qho khoom me me txav mus rau saum toj ua raws li qhov sib npaug y = 8t - t 2 , nrog y thiab t hauv meters thiab vib nas this, raws li. Qhov ceev ntawm cov khoom ntawm t = 2 vib nas this yog…
A. 2 ms -1
B. 4 ms -1
C. 8 ms -1
D. 12 ms -1
E. 16 ms -1
Kev Sib Tham
y = 8t – t2
v = 8 – 2t
Qhov ceev ntawm cov khoom ntawm t = 2 vib nas this:
v = 8 – 2t = 8 – 2(2) = 8 – 4 = 4 m/s.
Cov lus teb yog B.
3. Cov Lus Nug Txog Kev Xeem SMA/MA Xyoo 2017
Saib ntawm daim ntawv teev cov ntaub ntawv ceev rau peb yam khoom hauv qab no!
Raws li lub rooj, nws tuaj yeem xaus lus tias qhov khoom uas muaj qhov nrawm tshaj plaws yog ...
A. Khoom A rau t 1 – t 2
B. Khoom A rau t 2 – t 3
C. Khoom B rau t 1 – t 2
D. Khoom C rau t 1 – t 2
E. Khoom C rau t 2 – t 3
Kev Sib Tham
Khoom A: qhov ceev ntawm khoom nce 4 m/s txhua 2 vib nas this lossis 2 m/s txhua 1 vib nas this = 2 m/s 2.
Khoom B: qhov ceev ntawm khoom nce 5 m/s txhua 2 vib nas this lossis 2,5 m/s txhua 1 vib nas this = 2,5 m/s 2.
Khoom C: qhov ceev ntawm khoom txo qis 2 m/s txhua 2 vib nas this lossis 1 m/s txhua 1 vib nas this = -1 m/s 2.
Cov lus teb yog C.
