The circle with centre at the origin Student activity Play

The circle with centre at the origin Whiteboard exercise Play

The circumference and the astonishing number Pi Student activity Play

The circumference and the astonishing number Pi Whiteboard exercise Play

The common points of the disc and the coordinate axes Student activity Play

The C–X bond (2) Student activity Play

The defects of lenses Student activity Play

The density of matter inside the atomic nucleus of arsenic Whiteboard exercise Play

The density of matter inside the atomic nucleus of cobalt Whiteboard exercise Play

The density of matter inside the atomic nucleus of vanadium Whiteboard exercise Play

The distance between the centres of circles Student activity Play

The effect of atomic radius on the reactivity of Group 2 metals Animation Play

The efficiency of the energy conversion process Student activity Play

The energy levels of hydrogen atom Simulation Play

The energy levels of hydrogen atom Student activity Play

The energy of a tungsten filament Animation Play

The equation of a circle with centre at an arbitrary point Simulation Play

The equation of a circle with centre at an arbitrary point Student activity Play

The equation of a circle with centre at the origin Student activity Play

The equation of the circle with centre at an arbitrary point Whiteboard exercise Play

The exact values Whiteboard exercise Play

The First Law of Thermodynamics Whiteboard presentation Play

The First Law of Thermodynamics Class activity Play

The first tangent theorem – perpendicularity Student activity Play

The focal length and the shape of a lens Animation Play