

InterviewSolution
Saved Bookmarks
1. |
A body weighs `W_(1)` in a liquid of density `rho_(1)` and `W_(2)` in a liquid of density `rho_(2)`. What is the weight of body in a liquid of density `rho_(3)`? |
Answer» let m be the mass of the body, V be its volume and `rho` be its density. So `V=m//rho`. Weight of body in air, `W=mg`. Effective weight of the body when completely immersed in a liquid of density `rho_(1)` is `W_(1) = mg - V rho_(1) g =mg - (m)/(rho) rho_(1)g` `= mg(1-(rho_1)/(rho))=W(1-(rho_1)/(rho))` ...(i) similarly, `W_(2) = W(1-(rho_2)/(rho))` ..(ii) and `W_(3) = W(1-(rho_3)/(rho))` ..(iii) Using (i),(ii) and (iii) , we get `W_(3) = W_(2) (rho_(3)-rho_(1))-W_(1)(rho_(3)-rho_(2))/(rho_(2)-rho_(1))`. |
|