Circumference and Arc Length

Front

What is the formula for the circumference of a circle?

Back

C = 2πr, where C is the circumference and r is the radius.

Front

What is the value of π (pi) approximately?

Back

π ≈ 3.14.

Front

How do you calculate the circumference of a circle with a diameter of 10 cm?

Back

C = πd = 3.14 × 10 = 31.4 cm.

Front

What is the relationship between radius and diameter?

Back

Diameter (d) = 2 × Radius (r).

Front

What is arc length in a circle?

Back

Arc length is the distance along the curved line of the arc.

Front

How do you find the arc length given the radius and central angle?

Back

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

Front

What is the circumference of a circle with a radius of 7 cm?

Back

C = 2πr = 2 × 3.14 × 7 = 43.96 cm.

Front

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

Back

C = 2πr = 2 × 3.14 × 5 = 31.4 inches.

Front

What is the arc length of a circle with a radius of 3 cm and a central angle of 90 degrees?

Back

Arc Length = (90/360) × 2π(3) = 4.71 cm.

Front

What is the formula to find the central angle from arc length?

Back

θ = (Arc Length / (2πr)) × 360.