Consider the same wing operating at 100 m/s. At a point on the chord, the pressure coefficient is Cp = -0.6. Find the pressure difference (Δp) at that point.

Steps to Solve

1. Understanding the pressure coefficient formula

The pressure difference ($\Delta p$) can be calculated using the formula: $$ \Delta p = C_p \cdot \frac{1}{2} \rho V^2 $$ where $C_p$ is the pressure coefficient, $\rho$ is the air density, and $V$ is the velocity.

2. Identify the variables

In this problem:

• Given $C_p = -0.6$
• Given $V = 100 \text{ m/s}$

Assuming the air density ($\rho$) at standard conditions is approximately $1.225 \text{ kg/m}^3$.

3. Substituting values into the formula

Now, substituting the values into the equation:

$$ \Delta p = -0.6 \cdot \frac{1}{2} \cdot 1.225 \cdot (100)^2 $$

4. Calculate the right side

First, calculate $ \frac{1}{2} \cdot 1.225 \cdot (100)^2 $:

$$ \frac{1}{2} \cdot 1.225 \cdot 10000 = 6125 $$

Now substitute this back to find $\Delta p$:

$$ \Delta p = -0.6 \cdot 6125 $$

5. Final Calculation

Calculating the final pressure difference:

$$ \Delta p = -3675 \text{ Pa} $$