Math CentralQuandaries & Queries


Question from Serenity, a student:

A denotes the area of a sector of a circle of radius r formed by the central angle theta.
Find the area A if r=10 meters and theta = 1/2 radians.


The area of a circle of radius r meters is π r2 square meters. The central angle of one entire revolution of the circle is 360 degrees or 2π radians. Hence 1/2 a radian is 1/(4π) of the way around the circle. Thus the area of your sector is 1/(4π) of the area of the circle.

I hope this helps,

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