Exploring Arc Lengths and Perimeters

What is the arc length of a circle with a radius of 10 cm and a central angle of 60 degrees?

• 20 cm

• 5π cm

Calculate the circumference of a circle with a diameter of 14 cm.

Give your answer to 2 decimal places.

Ans: (a)   cm

If a sector has a radius of 5 m and a central angle of 90 degrees, what is its perimeter?

• 15 m

• 10 + 5π m

• 7.5 m

• 10 + 2.5π m

Determine the arc length of a circle with a radius of 12 inches and a central angle of 120 degrees.

• 6π inches

• 8π inches

• 10π inches

• 12 inches

What is the circumference of a circle with a radius of 7.5 m?

Ans: (a)   m (to 3sf)

A sector has a radius of 10 cm and a central angle of 150 degrees. Calculate its perimeter.

• 15 cm

• 20π +20 cm

• 30 cm

Calculate the perimeter of a sector of a circle with a radius of 6 cm and a central angle of 30 degrees.

• 6π cm

• π + 6 cm

• π + 12 cm

• 12 cm

What is the arc length of a circle with a radius of 15 cm and a central angle of 180 degrees?

• 15π cm

• 45π cm

• 75π cm

• 30π cm

Find the circumference of a circle with a diameter of 20 inches.

• 50 inches

• 62.83 inches

• 78.54 inches

• 25.12 inches

If a sector has a radius of 4 m and a central angle of 60 degrees, what is its perimeter?

• 12 m

• 8 + (4π/3) m

• 8 + 2π m

• 4 + 2π m