Circle Parts

• Mathematics
• Lower Secondary (Key Stage 3)

Circle parts 

Area, circumference and degrees

what are the differet parts of a circle

1. sector
2. diameter
3. Segment
4. radius

1. sector
2. diameter
3. radius
4. chord

1. sector
2. circumference
3. arc
4. chord

1. sector
2. segment
3. Arc
4. chord

1. sector
2. segment
3. tangent
4. chord

1. sector
2. segment
3. Arc
4. chord

1. sector
2. segment
3. tangent
4. diameter

1. sector
2. circumference
3. tangent
4. diameter

Circle

The parts of a circle are the radius, diameter, circumference, arc, chord, secant, tangent, sector and segment. A round plane figure whose boundary consists of points equidistant from a fixed point.

What is the diameter of a circle?

1. A line segment going from one point of the circumference to another but does not go through the centre.
2. The distance across the circle going through the centre.
3. The distance from the centre of a circle to the outside.
4. The distance once around the circle.

What is the radius of a circle?

1. A line segment going from one point of the circumference to another but does not go through the centre.
2. The distance across the circle going through the centre.
3. The distance from the centre of a circle to the outside.
4. The distance once around the circle.

Radius of A Circle

Radius is half the diameter

What is the relationship between the radius and the diameter of a circle

1. Diameter = 2 x Radius
2. Diameter = Radius ÷ 2
3. Diameter = √Radius
4. Diameter = Radius²

What is the circumference of a circle?

1. A line segment going from one point of the circumference to another but does not go through the centre.
2. The distance across the circle going through the centre.
3. The distance from the centre of a circle to the outside.
4. The distance once around the circle.

What is the area of a circle?

1. A line segment going from one point of the circumference to another but does not go through the centre.
2. The space inside a 2D shape.
3. The distance from the centre of a circle to the outside.
4. The distance once around the circle.

What is the diameter of a circle if its radius is 6cm?

1. 3cm
2. 12cm
3. 10cm
4. 12mm

Using the diameter

Use the formula C = πd to find the circumference if you know the diameter. In this equation, "C" represents the circumference of the circle, and "d" represents its diameter. 

That is to say, you can find the circumference of a circle just by multiplying the diameter by pi. Plugging π into your calculator will give you its numerical value, which is a closer approximation of 3.14 or 22/7.

Diameter means a straight line segment that passes through the center of the circle and has its endpoints on the sides of the circle.

What is the circumference of a circle with a radius of 3cm?
(Remember C=2πr, where π=3.14)

1. 16.85cm
2. 19.85cm
3. 17.85cm
4. 18.85cm

What is the circumference of a circle with a diameter of 10cm?
(Remember C=2πr, where π=3.14)

1. 30.42cm
2. 31.42cm
3. 32.42cm
4. 33.42cm

What is the area of a circle with a radius of 4cm?

What is the area of the circle

π=3.14

What is the area of the circle

π=3.14

What is the area of the circle

π=3.14

How many degrees are there in one quarter of a circle?

1. 90 degrees
2. 180 degrees
3. 270 degrees
4. 360 degrees

How many degrees are three quarters of a circle?

1. 90 degrees
2. 180 degrees
3. 270 degrees
4. 360 degrees

How many degrees in 2 complete circles?

1. 180 degrees
2. 360 degrees
3. 540 degrees
4. 720 degrees

How many degrees in 2/3 a circle?

1. 120 degrees
2. 240 degrees
3. 360 degrees
4. 420 degrees

How many degrees in 1/10 of a circle?

1. 30 degrees
2. 36 degrees
3. 45 degrees
4. 90 degrees

Activities

Finding the circumference using the radius and diameter

Finding the area using the radius (and diameter)

Finding the area of a circle GCSE questions