4 Piv txwv ntawm Cov Hlab Nkaus U-puab Txuas Nrog Cov Hlab Nkaus
1. Ob lub thoob A thiab B puv nrog cov kua dej ntawm qhov sib txawv, raws li pom hauv daim duab. Yog tias qhov siab ntawm qab ntawm A sib npaug rau 4/5 siab ntawm lub hauv paus ntawm B thiab qhov ceev kua A = 1000 kg m-3 , ces qhov ceev ntawm cov kua ntawm B yog ...
A. 1250 kg m-3
B. 2500 kg m-3
C. 3000 kg m-3
D. 4000 kg m-3
E. 5000 kg m-3
Kev Sib Tham
Nws paub tias:
Lub zog siab ntawm lub hauv paus ntawm A (PA) = 4/5 npaug ntawm qhov siab ntawm lub hauv paus ntawm B (4/5 PB)
Qhov ceev ntawm cov kua A (ρA) = 1000 kg/m²-3
Nug: Qhov ceev ntawm cov kua B (ρB)
Lus teb:
Cov mis rau hydrostatic siab ntawm cov kua A yog PA = ρA ghA
RCov mis rau hydrostatic siab ntawm cov kua B yog PB = ρB ghB
Lub zog siab ntawm lub hauv paus ntawm A = 4/5 npaug ntawm qhov siab ntawm lub hauv paus ntawm B:

Qhov siab ntawm cov kua ntawm A = qhov siab ntawm cov kua ntawm B yog li ntawd hA thiab hB tshem tawm ntawm qhov sib npaug.
Qhov kev nrawm vim yog lub ntiajteb txawj nqus g yog tib yam yog li nws raug tshem tawm ntawm qhov sib npaug.
5 (ρA) = 4 (ρB)
5 (1000) = 4 (ρB)
ρB = 5000 / 4
ρB = 1250
Qhov ceev ntawm cov kua ntawm B yog 1250 kg m-3
Cov lus teb yog lawm yog A.
2. Ib lub raj U-tube puv nrognrog ob lub kua sib txawv raws li pom hauv daim duab hauv qab no! Yog tias qhov ceev ρ1 = 0,8 g.cm-3, ρ2 = 1 g.cm-3, thiab h1 = 10 cm, ces qhov siab h2 yog ....
A. 5 cm
B. 6 cm
C. 7 cm
D. 8 cm
E. 10 cm
Kev Sib Tham
Nws paub tias:
Qhov Ceev 1 = 0,8 g.cm-3
Qhov Ceev 2 = 1 g.cm-3
Qhov siab 1 = 10 cm
Nug: Qhov siab 2
Lus teb:

Cov lus teb yog D.
3.
Ib lub raj xa dej U puv nrog ob hom kua sib txawv raws li pom hauv daim duab hauv qab no! Yog tias qhov ceev p1 = 0,8 g.cm-3, p2 = 1 g.cm-3, thiab h1 = 10 cm, ces qhov siab h2 yog ....
A. 5 cm
B. 6 cm
C. 7 cm
D. 8 cm
E. 10 cm
Kev Sib Tham
Nws paub tias:
Qhov Ceev 1 = 0,8 g.cm-3
Qhov Ceev 2 = 1 g.cm-3
Qhov siab 1 = 10 cm
Nug: Qhov Siab 2
Lus teb:
Cov lus teb yog D.
4.
Ua tib zoo saib daim duab hauv qab no:
Ib lub raj U-tube pib puv nrog dej nrog qhov ceev ntawm 1000 kg.m-3 Tom qab ntawd, cov roj ua noj raug nchuav rau hauv ib lub kav dej kom qhov chaw ruaj khov zoo li daim duab. Yog tias qhov siab ntawm cov roj kem yog 8 cm thiab cov dej kem yog 5 cm, qhov ceev ntawm cov roj ua noj yog….
A. 520 kg.m-3
B. 525 kg.m-3
C. 600 kg.m-3
D. 625 kg.m-3
E. 720 kg.m-3
Kev Sib Tham
Nws paub tias:
Qhov ceev ntawm dej = 1000 kg.m-3
Qhov siab ntawm dej = 5 cm
Qhov siab ntawm cov roj ua noj = 8 cm
Lus Nug: Qhov ntom ntawm cov roj ua noj
Lus teb:
Cov lus teb yog D.
Qhov chaw nug lus:
Cov Lus Nug Txog Kev Xeem Physics Hauv Tebchaws Rau Tsev Kawm Ntawv Theem Siab/Tsev Kawm Ntawv Theem Siab Ua Haujlwm