Area & Circumference of Circles

Front

What is the area of a semicircle?

Back

The area of a semicircle is half the area of a full circle, calculated using the formula: Area = (π * r²) / 2, where r is the radius.

Front

What does the 'area' of a circle mean?

Back

The area of a circle refers to the space that the circle occupies, measured in square units.

Front

What is the formula to calculate the area of a circle?

Back

Area = π * r², where r is the radius of the circle.

Front

What is the circumference of a circle?

Back

The circumference of a circle is the distance around the circle, calculated using the formula: Circumference = 2 * π * r, where r is the radius.

Front

What is the formula to calculate the circumference of a semicircle?

Back

Circumference of a semicircle = (π * r) + (2 * r), where r is the radius.

Front

If a circle has a radius of 3 m, what is its area?

Back

Area = π * (3 m)² = 28.27 m² (approximately).

Front

If a circle has a radius of 4 m, what is its circumference?

Back

Circumference = 2 * π * 4 m = 25.13 m (approximately).

Front

What is the relationship between diameter and radius?

Back

The diameter of a circle is twice the length of the radius: Diameter = 2 * r.

Front

How do you find the radius if you know the area of a circle?

Back

To find the radius from the area, use the formula: r = √(Area / π).

Front

What is the area of a circle with a diameter of 10 m?

Back

Radius = 5 m; Area = π * (5 m)² = 78.54 m² (approximately).