It looks like you're trying to express a formula involving the variables $V$, $t$, $\pi$, $p$, $r$, $l$, and $n$. Based on your input, I think you might be referring to the Poiseuille's law, which describes the flow of a fluid through a cylindrical pipe.

The correct form of Poiseuille's law is:

$\frac{V}{t} = \frac{\pi p r^4}{8 \eta l}$

Where:

• $V/t$ represents the volumetric flow rate ($Q$).
• $\pi$ is a constant (approximately 3.14159).
• $p$ is the pressure difference between the two ends of the pipe.
• $r$ is the radius of the pipe.
• $\eta$ (often written as $\mu$) is the dynamic viscosity of the fluid.
• $l$ is the length of the pipe.

It seems like you have a version with a typo where "pie" is used instead of $\pi$ and "n" instead of $\eta$, but the formula is likely aiming to describe fluid flow through a pipe.

Would you like further clarification on this, or is there a specific part of the formula you're looking to solve for?

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Follow-up questions:

1. How is Poiseuille's law used to calculate flow rate in real-world applications?
2. What are the units for each of these variables in the formula?
3. How does viscosity $\eta$ affect the flow rate of a fluid in a pipe?
4. What happens to the flow rate if the radius of the pipe is doubled?
5. What is the difference between laminar and turbulent flow in pipes?

Tip:

The flow rate in pipes governed by Poiseuille’s law is highly sensitive to the radius of the pipe, making it a critical factor for understanding fluid dynamics.