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**Related Pages**Angles In A CircleAngles and Intercepted ArcsCirclesConic Sections: CirclesMore Geometry Lessons

### Arc the A Circle

An **arc** is any kind of connected part of the one of a circle.

In the diagram above, the component of the circle native M come N forms an arc. The is dubbed arc MN.

An arc can be a boy arc, a semicircle or a major arc.

A semicircle is an arc that is fifty percent a circle.A minor arc is an arc that is smaller sized than a semicircle.A major arc is one arc that is larger than a semicircle.### Central Angle

A main angle is one angle whose vertex is in ~ the facility of a circle.

In the chart above, the main angle for arc MN is 45°.

The amount of the main angles in any kind of circle is 360°.

### Arc Measure

The measure up of a semicircle is 180°.

The measure up of a young arc is same to the measure of the main angle that intercepts the arc.We can additionally say that the measure up of a young arc is same to the measure of the central angle thatis subtended through the arc. In the diagram below, the measure up of arc MN is 45°.

The measure up of the major arc is same to 360° minus the measure up of the associated minor arc.

The following video shows how to determine semicircle, young arc and significant arc and also their measures.

### Arc length Formula

The arc length is the distance along the part of the one that makes up the arc.

The following diagram offers the recipe to calculation the arc size of a circle because that angle measuresin degrees and angle measured in radians. Scroll down the web page for an ext examples and also solutions.

### Arc Measure given In Degrees

Since the arc length is a portion of the circumference of the circle, we deserve to calculateit in the complying with way. Find the one of the circle and then multiply by the measureof the arc divided by 360°. Remember that the measure of the arc is same to the measureof the central angle.

The formula because that the arc length of a one is:

where r is the radius that the circle and also m is the measure up of the arc (or central angle) in degrees.

Worksheetto calculate arc length and area that a sector (degrees).

### Arc Measure given In Radians

If the measure of the arc (or main angle) is given in radians, then theformula because that the arc length of a one is the product the the radius and the arc measure.

Arc size = r × m

where r is the radius the the circle and also m is the measure of the arc (or main angle) in radians.

The over formulas enable us come calculate any one the the values offered the other two values.

Worksheetto calculation arc length and area of ar (radians).

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### Calculate Arc Length given Measure the Arc In Degrees

From the formula, we can calculate the length of the arc.

**Example:**

If the one of the adhering to circle is 54 cm, what is the length of the arc ABC?