Circles Circles Circles

Front

What is a circle?

Back

A circle is a shape consisting of all points in a plane that are at a given distance from a fixed point, called the center.

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

What is the diameter of a circle?

Back

The diameter is a line segment that passes through the center of the circle and has its endpoints on the circle. It is twice the length of the radius.

Front

How do you calculate the area of a circle?

Back

The area of a circle can be calculated using the formula A = πr², where r is the radius.

Front

What is the circumference of a circle?

Back

The circumference is the distance around the circle, calculated using the formula C = 2πr or C = πd, where d is the diameter.

Front

What is a chord in a circle?

Back

A chord is a line segment whose endpoints both lie on the circle.

Front

What is a tangent to a circle?

Back

A tangent is a line that touches the circle at exactly one point.

Front

What is the relationship between the radius and diameter?

Back

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

Front

What is the formula for the area of a circle with a radius of 3 cm?

Back

Using the formula A = πr², the area is A = π(3)² = 28.26 cm².

Front

What is the center of a circle?

Back

The center of a circle is the fixed point from which all points on the circle are equidistant.