The diagram shows Venturi meter through which water is flowing. The speed of water at X is 2 cm/sec. The speed of water at Y in cm/s (taking g=1000 cm/sec²) is_______

The speed of water at sections X and Y should be equal. Applying

Bernoulli's equation $P_1+\frac{1}{2}\rho v_1^2=P_2+\frac{1}{2}\rho v_2^2$

$\begin{array}{l}\Rightarrow \frac{1}{2}\rho \left(v_2^2-v_1^2\right)=P_1-P_2=h\rho g\\ v_2^2=v_1^2+2gh\\ v_2=\sqrt{(2{)}^2+2\times 1000\times 0.51}=32\mathrm{cm}/\mathrm{s}\end{array}$