Rate of flow \(\propto\) pressure difference \(\times(\text { radius })^4\)
\(Q \propto P \times a^4\) \(\left\{\because Q=\frac{\pi P r^4}{8 \eta L}\right\}\)
So, \(\frac{Q_1}{Q_2}=\frac{P_1 a_1^4}{P_2 a_2^4}\)
\(\frac{Q_1}{Q_2}=\frac{P \times a^4}{4 P \times\left(\frac{a}{4}\right)^4}=\frac{64}{1}\)
\(\therefore Q_2=\frac{Q_1}{64}=\frac{Q}{64}\)