CIRCLES, ARC LENGTH, AND SECTORS

Front

What is the distance along an arc measured in linear units?

Back

Arc length

Front

What is the formula for the circumference of a circle?

Back

Circumference = 2πr, where r is the radius.

Front

What is the area of a circle?

Back

Area = πr², where r is the radius.

Front

What is a sector of a circle?

Back

A sector is a portion of a circle enclosed by two radii and the arc between them.

Front

How do you calculate the area of a sector?

Back

Area of a sector = (θ/360) × πr², where θ is the central angle in degrees.

Front

What is the relationship between arc length and radius?

Back

Arc length = (θ/360) × 2πr, where θ is the central angle in degrees.

Front

What is the formula for the area of a sector in radians?

Back

Area of a sector = (1/2)r²θ, where θ is the central angle in radians.

Front

What is the definition of a tangent line to a circle?

Back

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

Front

What is the diameter of a circle?

Back

The diameter is the distance across the circle through its center, equal to 2 times the radius.

Front

What is the relationship between the radius and diameter?

Back

Diameter = 2 × Radius.