Answer:
v₂ =[tex]( \frac{r_1}{r_2})^2 \ v_1[/tex]
Explanation:
This phenomenon is explained by the continuity equation in fluids
v₁A₁ = v₂A₂
where the subscript 1 is for the input narrow part and the subscript 2 for the wide part
v₂ = [tex]\frac{A_1}{A_2} v_1[/tex]
consider the cross section at each point
A₁ = π r₁²
A₂ = π r₂²
we substitute
v₂ =[tex]( \frac{r_1}{r_2})^2 \ v_1[/tex]
therefore the exit velocity is less than the entrance velocity of the fluid.
We can also analyze the situation using Bernoulli's equation
P₁ + ρ g v₁² + ρ g y₁ = P₂ + ρ g v₂² + ρ g y²
if we assume a horizontal system y₁ = y₂
P₁-P₂ = ρ g (v₂² - v₁²)