Question

The opening near the bottom of the vessel shown in the
figure has an area A. A disc is held against the opening to
keep the liquid from running out. Let F, be the net force
on the disc applied by liquid and air in this case. Now the
disc is moved away from the opening a short distance. The
liquid comes out and strikes the disc inelastically. Let F,
be the force exerted by the liquid in this condition. Then
F1/F2
Fig. 4.183​

Answer 1

Answer:

1/2

Explanation:

Let ρ the density of liquid. Then

F1=(ΔP)A=ρghA

In the second case, F2=rate of change of momentum

= mass of water striking per sec x velocity

= (Av × ρ) × v = Aρv^2 =Aρ$(\sqrt{2pgh} )^2$

= Aρ×2gh

 $\frac{F1}{F2} = \frac{1}{2}$