In a wind tunnel experiment the pressure on the upper and lower surfaces of the wings are 0.90`xx 10^(5)` Pa and 0.91 `xx10^(5)`Pa respectively .If the area of the wings is `40 m^(2)` the net liftng forcw on the wing is

Options

A. `2xx 10^(4)`N
B. `4xx 10^(4)`N
C. `6 xx 10^(4)`N
D. `8 xx 10^(4)`N

Explanation

To solve the problem of calculating the net lifting force on the wing in a wind tunnel experiment, we will follow these steps:

### Step 1: Write down the given data
- Pressure on the upper surface of the wing, \( P_{upper} = 0.90 \times 10^5 \, \text{Pa} \)
- Pressure on the lower surface of the wing, \( P_{lower} = 0.91 \times 10^5 \, \text{Pa} \)
- Area of the wings, \( A = 40 \, \text{m}^2 \)

### Step 2: Calculate the pressure difference
The net lifting force is determined by the difference in pressure between the lower and upper surfaces of the wing. We can calculate the pressure difference (\( \Delta P \)) as follows:
\[ \Delta P = P_{lower} - P_{upper} \]
Substituting the values:
\[ \Delta P = (0.91 \times 10^5) - (0.90 \times 10^5) = (0.01 \times 10^5) \, \text{Pa} = 1.0 \times 10^3 \, \text{Pa} \]

### Step 3: Calculate the net lifting force
The net lifting force (\( F \)) can be calculated using the formula:
\[ F = \Delta P \times A \]
Substituting the values we have:
\[ F = (1.0 \times 10^3 \, \text{Pa}) \times (40 \, \text{m}^2) = 4.0 \times 10^4 \, \text{N} \]

### Final Answer
The net lifting force on the wing is:
\[ F = 4.0 \times 10^4 \, \text{N} \]

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