# I Tank Drainage and Area

1. Mar 13, 2016

### UMath1

Using Bernoulli's equation to calculate the velocity of fluid draining from a tank seems to give no weightage to the area of the drainage hole. But based on the mass continuity principle, the area of the hole should have an impact. Does the area of a drainage hole have an impact on the fluid velocity or not? And why does it appear to be neglected in velocity calculations?

2. Mar 13, 2016

### BvU

The drainage opening does appear in the velocity, e.g. here. What calculation scheme are you referring to ?

3. Mar 14, 2016

### UMath1

Yes thats a first. But still it does not appear in the equations used to calculate the velocity which is Bernoulli's equation. Bernoulli's equation simplifies to V =(2gh)^(1/2). This does not include the diameter of the hole.

4. Mar 14, 2016

### Staff: Mentor

Velocity isn't volumetric flow rate. The volumetric flow rate depends on the velocity and area. Bernoulli's equation relates velocity to pressure.

It is similar to the difference between pressure and force. You don't necessarily need to relate them.