Saved Bookmarks
| 1. |
Water flows through a horizontal tube as shown in figure. If the difference of heights of water colun in the vertical tubes is 2 cm and the area of cross section at A and B are `4cm^2 and 2cm^2` respectively, find the rate of flow of water across any section. A. `130xx10^(-6)m^(3)//s`B. `146xx10^(-6)m^(3)//s`C. `160xx10^(-6)m^(3)//s`D. `170xx10^(-6)m^(3)//s` |
|
Answer» Correct Answer - B `v_(A)a_(A)=v_(B)xxa_(B)=v_(A)xx4=v_(B)xx2v_(B)=2v_(A)`………i Again `1/2, rhov_(A)^(2)+rhogh_(A)+p_(A)=1/2rhov_(B)^(2)+rhogh_(B)+p_(B)` `implies1/2rhog_(A)^(2)+p_(A)=1/2rhov_(B)^(2)+p_(B)` (as `h_(A)=h_(B)`) `impliesp_(A)-p_(B)=1/2rho(v_(B)^(2)-v_(A)^(2))=1/2xx1xx(4v_(A)^(2)-v_(A)^(2))` `implies2x1xx1000=1/2xx1xx3v_(A)^(2)` `p_(A)=p_(B)=2cm` of water column `=2xx1xx1000dyn//cm^(2)` `:.v_(A)=sqrt(4000/3)=36.51cm//s` So, rate of flow `=V_(a)a_(A)=36.51xx4=146cm^(3)//s`. |
|