Arc length and sector area

Change the radius and the angle to see the arc length, the sector area and the angle in radians.

Learn arc length properly

StudyAI writes clear notes on any topic you study, with practice quizzes, past-paper questions explained, and interactive models like this one in the notes.

Get free notes and a quiz on this
Free to start. No card needed.

Questions students ask

How do you convert degrees to radians?

Multiply by π/180. A full turn of 360° is 2π radians.

What formula does it use?

Arc = θ/360 × 2πr = rθ; sector area = θ/360 × πr² = ½r²θ (θ in radians).

Free notes on arc length

More mathematics tools

Percentage change calculator
Calculate percentage increase or decrease and the multiplier, and learn reverse percentages. Free percentage c…
Circle calculator: area and circumference
Calculate the area, circumference and diameter of a circle from its radius. Free interactive circle calculator…
Speed, distance and time
Work out average speed from distance and time, in km/h and m/s. Free speed, distance and time calculator.
Arithmetic sequences and series
Find the nth term and the sum of an arithmetic sequence from the first term and common difference. Free sequen…
All interactive tools
Use this on your own site or class page

Copy this code. It is free to use, as long as the link stays.