In this video I demonstrate how to find the arc length and sector area of circles.
I first define what is meant by a circle sector and explain what is meant by a major and minor sectors and how both are portions or fractions of the total area of a circle.
I then look at how to find the area of a minor circle sector given the subtended angle Θ in degrees and the radius of a circle.
A brief demonstration of how to convert from degrees to radians and radians back to degrees is provided before moving on to find the circle sector area when given the radius of the circle and the subtended angle Θ in radians. I then show how the formula for the sector area is 1/2r²Θ when the subtended angle is in radians
I then demonstrate how to find the arc length of a minor sector of a circle and explain that the arc length is a portion or fraction of the circumference of a circle.
I demonstrate, when given the subtended angle in degrees and the radius, how to calculate the arc length of a circle sector.
The final part of the video explains and demonstrates how to find the arc length of a sector of a circle when given the radius and subtended angle in radians. It show how the formula s=rΘ is used to do this when working in radians.