Area and Circumference of a Circle

Front

What is the diameter of a circle?

Back

The diameter is a straight line that passes through the center of the circle and connects two points on its circumference. It is twice the length of the radius.

Front

If the radius of a circle is 8 cm, what is the diameter?

Back

16 cm

Front

What is the formula to find the diameter if the radius is known?

Back

Diameter = 2 × Radius

Front

If the diameter of a circle is 40 ft, what is the radius?

Back

20 ft

Front

What is the formula to find the radius if the diameter is known?

Back

Radius = Diameter / 2

Front

What is the area of a circle?

Back

The area of a circle is the space contained within its circumference, calculated using the formula: Area = π × Radius².

Front

If the radius of a circle is 10 ft, what is the area?

Back

Area = π × (10 ft)² = 314.16 ft² (approximately).

Front

What is the circumference of a circle?

Back

The circumference is the distance around the circle, calculated using the formula: Circumference = 2 × π × Radius.

Front

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

Back

Circumference = 2 × π × 5 cm ≈ 31.4 cm.

Front

What is π (pi)?

Back

π (pi) is a mathematical constant approximately equal to 3.14, representing the ratio of the circumference of a circle to its diameter.