Calculating the Length of an Arc
The length of an arc in a circle can be calculated using the formula:
Arc Length (L) = (θ/360) × (2 × π × r)
Where:
- θ = the central angle in degrees
- r = the radius of the circle
- π (Pi) ≈ 3.14159
In this case, the radius (r) is given as 10 feet and the angle (θ) is 81 degrees. Now, let’s plug in these values into the formula:
L = (81/360) × (2 × π × 10)
First, we need to calculate the circumference of the circle, which is:
C = 2 × π × r = 2 × π × 10 = 20π
Now, substitute the values into the arc length formula:
L = (81/360) × (20π)
Now, calculate the fraction:
L = (81 × 20π) / 360
This simplifies to:
L = (1620π) / 360 = (9π) / 2
Finally, we can approximate the value of the arc length:
L ≈ 14.1372
So, the arc length of a circle with a radius of 10 feet subtended by an angle of 81 degrees is approximately 14.14 feet.