Making Waves 

Making Waves is an interactive physics package that helps students visualize and understand the motion and interference of transverse and longitudinal waves.
amplitude damping frequency interference longitudinal phase pulse superposition wave wavelength

GEOPosCalc 

GEOPosCalc makes easy and simple a job normally tedious in other products, the conversion from geographic positions to UTM and vice versa.
gps latitude longitude calculator conversor coordinate datum utm mercator position