Pieces of a Circle Examples

What is the arc length of a portion of a 10 cm diameter circle cut by a 45° angle?

The formula for the arc length when we're working in degrees is: We have a diameter of 10 cm, which means our radius is 5 cm. Plugging in our values, we get: = 1.25π

What is the arc length of a sector with an angle of in a circle with a radius of 5 units?

Finding the arc length is easy when we have the angle in radians. Just multiply it and the radius together.

What is the area of a sector of a circle measuring 6 in across that is cut by an angle of 195 degrees?

We don't want the total area, we just want of the area. The total area is π(3)² = 9π. so the area of the sector is 4.875π.

What is the arc length of a sector with an angle of in a circle with a diameter of 22 in?

The area of a sector in radians is . The radius is 11 in, so: