Question

When kerosene and coconut oil of coefficients of viscosity 0.002 and 0.0154 Nsm${}^{-2}$ are allowed to flow through the same pipe under the same pressure difference in the same time interval, the coconut oil collected is 1 litre in volume. The volume of kerosene that flows is:

• A. 5.5 lit
• B. 6.6 lit
• C. 7.7 lit
• D. 8.8 lit

Answer 1

Answer: (C)

7.7 lit

When kerosene and coconut oil flow through same conditions, the volume collected will be i ratio to the flow rate of kerosene and coconut oil respectively.
$\frac{1}{x}=\frac{\frac{\pi \left(P\right)r^4}{{\eta }_{1}8L}}{\frac{\pi \left(P\right)r^4}{{\eta }_{2}8L}}\Rightarrow \frac{1}{x}=\frac{{\eta }_2}{{\eta }_1}$
$\Rightarrow \frac{1}{x}=\frac{0.002}{0.0154}\Rightarrow x=7.7Liters$