Circumference, Arc Measure, and Arc Length

Front

What is the formula for the circumference of a circle?

Back

C = 2πr, where C is the circumference and r is the radius.

Front

What is the circumference of a circle with a radius of 5 inches?

Back

31.4 inches.

Front

What is the area of a circle with a radius of 7 cm?

Back

154 cm².

Front

If the diameter of a circle is 15 inches, what is the circumference?

Back

47.1 inches.

Front

What is the relationship between diameter and radius?

Back

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

Front

What is an arc in a circle?

Back

An arc is a portion of the circumference of a circle.

Front

What is the definition of a diameter?

Back

A diameter is the longest line in a circle that passes through the center.

Front

How do you find the radius if you know the circumference?

Back

Use the formula r = C / (2π).

Front

What is the formula for the area of a circle?

Back

A = πr², where A is the area and r is the radius.

Front

If the circumference of a circle is 31.4 cm, what is the radius?

Back

5 cm.