A series of activities to build up intuition on the mathematics of friction.

Which parts of these framework bridges are in tension and which parts are in compression?

In this short problem we investigate the tensions and compressions in a framework made from springs and ropes.

Gravity on the Moon is about 1/6th that on the Earth. A pole-vaulter 2 metres tall can clear a 5 metres pole on the Earth. How high a pole could he clear on the Moon?

How high will a ball taking a million seconds to fall travel?

See how little g and your weight varies around the world. Did this variation help Bob Beamon to long-jumping succes in 1968?

Whirl a conker around in a horizontal circle on a piece of string. What is the smallest angular speed with which it can whirl?

A collection of problems related to the mathematics of fundamental physics.

Invent shapes with different numbers of stable and unstable equilibrium points