DfE statement G9 · Geometry and measures

Circle definitions and parts of a circle

Both tiersNon-calculator

Circle definitions and parts of a circle is content statement G9 of the DfE GCSE mathematics subject content, in the geometry area. It is on both tiers, and it is examined without a calculator. Below is what the specification actually requires, the 3 mistakes that cost marks on this topic most often, and practice questions written to the statement — original questions, not past papers.

What the specification says

The DfE subject content for GCSE mathematics states, verbatim: "Identify and apply circle definitions and properties, including: centre, radius, chord, diameter, circumference, tangent, arc, sector and segment." (statement G9). Every awarding organisation — Pearson Edexcel, AQA and OCR — must cover it, so the wording is the same whichever specification your school follows.
— Department for Education, Mathematics: GCSE subject content and assessment objectives, statement G9

Tier

Both tiers. This statement is Foundation content, which means Higher students are examined on it too — Higher is Foundation plus more, never instead of it.

Calculator

This is non-calculator territory. Questions on it belong naturally on Paper 1, where written method is all you have — so practise it that way rather than with a calculator to hand.

Common mistakes

Confusing a chord with a diameter. Every diameter is a chord, but a chord only becomes a diameter when it passes through the centre.
Confusing a sector (bounded by two radii and an arc) with a segment (bounded by a chord and an arc).
Drawing a tangent through the centre. A tangent touches the circle at exactly one point and is perpendicular to the radius there.

Sample questions (10 of 30)

G9 · Circle definitions and parts of a circleQuestion 1 of 10 · 0 correct

Practice mode· no pressure · hints available

Geometry and measures

Beginner

A circle is drawn on a page. Write down how many radii can be drawn in the circle.

💡 Hints:

Foundation worksheet Higher worksheet Foundation geometry and measures practice Higher geometry and measures practice

Nearby statements

G1Geometric terms, notation and diagrams G2Ruler and compass constructions and loci G3Angle facts, parallel lines and polygons G4Properties of triangles and quadrilaterals G5Congruence criteria for triangles G6Geometric reasoning and simple proofs G7Transformations: rotation, reflection, translation, enlargementpart Higher G8Combinations of transformations and invarianceHigher only G10Circle theoremsHigher only G11Geometrical problems on coordinate axes G12Properties of 3D shapes G13Plans and elevations G14Standard units of measure G15Measuring, scale drawings and bearings G16Area of 2D shapes and volume of prisms G17Circles, composite shapes, spheres, pyramids and cones G18Arc lengths and sector areas G19Congruence and similarity: lengths, areas and volumespart Higher G20Pythagoras’ theorem and trigonometric ratiospart Higher G21Exact trigonometric values G22The sine rule and the cosine ruleHigher only G23Area of a triangle: ½ab sin CHigher only G24Translations as vectors

Questions people ask

Is circle definitions and parts of a circle on Foundation or Higher?

Both. It is Foundation content, so it can be asked on either tier.

Can I use a calculator for circle definitions and parts of a circle?

Not on Paper 1, which is where this normally appears. Paper 1 is non-calculator for both tiers and carries the same 80 marks as each of the other two papers.

What is the single most common mistake here?

Confusing a chord with a diameter. Every diameter is a chord, but a chord only becomes a diameter when it passes through the centre.

Are these past paper questions?

No. Every question is original, written to this DfE content statement and checked before publication. We do not host past papers or mark schemes.

Back to Geometry and measures at Foundation or at Higher.