Nature18 天
Wave Propagation in Periodic Structures
propagation of electro-magnetic waves along periodic circuits and filtering properties of such systems.
BBC3 天
KS2 Maths: The 11 Times Table
The 6 Times Table with Fred the Red. videoThe 6 Times Table with Fred the Red Manchester United's mascot, Fred the Red has a song and movement routine to help students learn the 6 times table.