What is the opening area of an aircraft's engine cylinder if the inside diameter or bore is 6 inches?

To determine the opening area of an aircraft's engine cylinder based on the bore diameter, we use the formula for the area of a circle:

[ A = \pi r^2 ]

where:

• ( A ) is the area,

• ( \pi ) is approximately 3.14,

• ( r ) is the radius of the circle.

First, since the diameter is given as 6 inches, you find the radius by dividing the diameter by 2:

[ r = \frac{6 \text{ inches}}{2} = 3 \text{ inches} ]

Next, plug the radius into the area formula:

[ A = \pi (3 \text{ inches})^2 ]

[ A = \pi \times 9 \text{ square inches} ]

[ A \approx 3.14 \times 9 \text{ square inches} ]

[ A \approx 28.26 \text{ square inches} ]

Rounding to two decimal places gives approximately 28.27 square inches. This value matches the correct answer and represents the opening area of the engine cylinder accurately based on the provided bore diameter.

In this context, the calculation demonstrates the application