Properties Of Solids And Liquids Question 236

Question: Two capillaries of same length and radii in the ratio 1 : 2 are connected in series. A liquid flows through them in streamlined condition. If the pressure across the two extreme ends of the combination is 1 m of water, the pressure difference across first capillary is

Options:

A) $ r _{1}+r _{2} $

B) $ r _{1}^{2}+r _{2}^{2} $

C) $ r _{1}^{4}+r _{2}^{4} $

D) None of these

Show Answer

Answer:

Correct Answer: D

Solution:

$ V=V _{1}+V _{2} $

therefore $ \frac{\pi Pr^{4}}{8\eta l}=\frac{\pi Pr _{1}^{4}}{8\eta l}+\frac{\pi Pr _{2}^{4}}{8\eta l} $

therefore $ r^{4}=r _{1}^{4}+r _{2}^{4} $ \ $ r={{(r _{1}^{4}+r _{2}^{4})}^{1/4}} $



NCERT Chapter Video Solution

Dual Pane