Foundation and Higher · parts of a circle

Can you name all
nine parts
of a circle?

most people mix up
two of them

start with the longest word —

Circumference

circum — means around

the distance all the way around

parts 1 to 3 of 9

From the centre

Centre: the point in the middle.

Radius: from the centre to the edge.

Diameter: edge to edge, through
the centre.

parts 4 to 6 of 9

Round the edge

Circumference: the whole edge.

Chord: edge to edge, missing the centre.

Tangent: touches the edge once.

parts 7 to 9 of 9

Pieces of the circle

Arc: part of the circumference.

Sector: a slice, between two radii.

Segment: the piece cut off by a chord.

the two everyone mixes up —

Sector

a slice that reaches the centre

Segment

cut off by a chord

Two radii? Sector.
One chord? Segment.

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