Physics - Fluid Question with Solution | TestHub

We have two (narrow) capillary tubes$T_1$and$T_2$. Their lengths are$l_1$and$l_2$and radii of the cross-section are$r_1$and$r_2$respectively. The rate of water under a pressure difference$P$through tube$T_1$is$8 {\mathrm{cm}}^3 {\mathrm{s}}^{-1}$. If$l_1 = 2l_2$and$r_1=r_2$, what will be the rate of flow when the two tubes are connected in series and the pressure difference across the combination is same as before(=$P$)