Spheres, cylinders and cones

There are 32 NRICH Mathematical resources connected to Spheres, cylinders and cones
Conical Bottle
problem

Conical Bottle

Age
14 to 16
Challenge level
filled star empty star empty star
A right circular cone is filled with liquid to a depth of half its vertical height. The cone is inverted. How high up the vertical height of the cone will the liquid rise?
In a Spin
problem

In a Spin

Age
14 to 16
Challenge level
filled star filled star filled star
What is the volume of the solid formed by rotating this right angled triangle about the hypotenuse?
Three Balls
problem

Three Balls

Age
14 to 16
Challenge level
filled star filled star empty star
A circle has centre O and angle POR = angle QOR. Construct tangents at P and Q meeting at T. Draw a circle with diameter OT. Do P and Q lie inside, or on, or outside this circle?
Ball Packing
problem

Ball Packing

Age
14 to 16
Challenge level
filled star filled star filled star
If a ball is rolled into the corner of a room how far is its centre from the corner?
2D-3D
problem

2D-3D

Age
16 to 18
Challenge level
filled star empty star empty star
Two circles of equal size intersect and the centre of each circle is on the circumference of the other. What is the area of the intersection? Now imagine that the diagram represents two spheres of equal volume with the centre of each sphere on the surface of the other. What is the volume of intersection?
Paint rollers for frieze patterns.
article

Paint rollers for frieze patterns.

Proofs that there are only seven frieze patterns involve complicated group theory. The symmetries of a cylinder provide an easier approach.
Curvature of Surfaces
article

Curvature of Surfaces

How do we measure curvature? Find out about curvature on soccer and rugby balls and on surfaces of negative curvature like banana skins.
Conic Sections
article

Conic Sections

The interplay between the two and three dimensional Euclidean geometry of conic sections is explored in this article. Suitable for students from 16+, teachers and parents.
Mouhefanggai
article

Mouhefanggai

Imagine two identical cylindrical pipes meeting at right angles and think about the shape of the space which belongs to both pipes. Early Chinese mathematicians call this shape the mouhefanggai.