Circle- parts, circumference, and area

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

If the radius of a circle is 5 cm, what is the diameter?

Back

The diameter is 10 cm (diameter = 2 × radius).

Front

What is the radius of a circle with a diameter of 16 inches?

Back

The radius is 8 inches (radius = diameter / 2).

Front

What is the formula for the circumference of a circle?

Back

Circumference = πd or Circumference = 2πr.

Front

If the diameter of a circle is 10 cm, what is the circumference?

Back

Circumference = π × 10 cm ≈ 31.4 cm.

Front

What is the area of a circle with a radius of 3 m?

Back

Area = πr² = π × (3 m)² ≈ 28.27 m².

Front

What is the relationship between diameter and radius?

Back

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

Front

What is the circumference of a circle with a radius of 4 feet?

Back

Circumference = 2π × 4 feet ≈ 25.13 feet.

Front

What does π (pi) represent in circle calculations?

Back

π is a constant approximately equal to 3.14, representing the ratio of the circumference to the diameter of a circle.

Front

If a circle has a circumference of 31.4 cm, what is its diameter?

Back

Diameter = Circumference / π ≈ 10 cm.