Arc Length/Circumference Circles (shortened, round 2DP)

Front

What is the distance around a circle?

Back

Circumference

Front

What is the formula for the circumference of a circle?

Back

C = πd or C = 2πr, where d is the diameter and r is the radius.

Front

What is the diameter of a circle?

Back

The diameter is the distance across the circle through its center, equal to twice the radius.

Front

What is the radius of a circle?

Back

The radius is the distance from the center of the circle to any point on its circumference.

Front

How do you calculate the circumference of a circle with a diameter of 12 inches?

Back

C = πd = π(12) ≈ 37.70 inches.

Front

What is a minor arc in a circle?

Back

A minor arc is the shorter arc connecting two points on a circle.

Front

How do you find the length of a minor arc?

Back

Arc length = (θ/360) × C, where θ is the central angle in degrees and C is the circumference.

Front

What is the circumference of a circle with a radius of 24 feet?

Back

C = 2πr = 2π(24) ≈ 150.80 feet.

Front

If the angle between two points on a circle is 165 degrees, how do you find the arc length?

Back

Arc length = (θ/360) × C, where C is the circumference of the circle.

Front

What is the relationship between the radius and diameter of a circle?

Back

The diameter is twice the radius (d = 2r).