[Music] chords segments arcs and sectors what these four words all have in common is that they're all special names for parts of a circle and in this video we're going to explain exactly what each one means let's draw out a circle and start with chords a chord is just a straight line that connects two points on the circumference of a circle so this line here is a chord because it's a straight line and it connects to this point on the circumference to this point on the circumference something to notice about this chord is that it effectively splits the circle into two parts and this actually brings us to our second term because we call each of these two parts a segment and more precisely we call the smaller part the minor segment and the larger part the major segment so if we took a couple more circles and drew chords across each one we'd be splitting them both into minor segments and major segments the third term we discover is the arc which is basically just a section of the circumference so if we took a circle and marked two points on the circumference then this small section between them would be an arc and this larger section on the other side would also be an arc and again we use our minor and major terminology so that we can call this bit in pink the minor arc and this but in purple the mage arc if we go back to our circle on the left we can apply our arc terms here as well because this part of the circumference around the minor segment will be the minor arc and this part around the major segments will be the major arc the last term we need to cover is the sector which is just a section of a circle as if you cut a slice of pizza or cake so it involves two radii they each go from the center out to the circumference connect together by an arc and just like segments and arcs we really have two sectors a smaller one called the minor sector which is bounded by the radii and the minor arc and a larger one called the major sector which is bounded by the same true radii and the major arc so to quickly summarize this video you can imagine it as if there are two different ways that you can cut a circle either straight across with a chord which will split the circle into a minor segment and a major segment or we can cut the circle by taking a slice using two radii which will result in a minor sector and a major sector in both cases though we'll also get a minor arc and a major arc anyway that's it for this video so if you want to practice some questions on this stuff or anything else in science or maths then do check out our website which you can get to using the link in the top right corner of the screen and otherwise we'll see you next time