question_answer 35)

                  An ideal fluid flows through a pipe of circular cross-section made of two sections with diameters 2.5 cm and 3.75 cm. The ratio of the velocities in the two pipes is                 (a) 9 : 4                                 (b) 3 : 2                 (c) \[\sqrt{3}:\,\sqrt{2}\]                              (d) \[\sqrt{2}:\,\sqrt{3}\]                

Answer:

                  (a) According to equation of country,                 \[{{a}_{1}}{{v}_{1}}=\,{{a}_{2}}{{v}_{2}}\] or \[\frac{{{v}_{1}}}{{{v}_{2}}}=\,\frac{{{a}_{2}}}{{{a}_{1}}}\,=\,{{\left( \frac{{{d}_{2}}}{{{d}_{1}}} \right)}^{2}}\]