“…For example, the time interval between two successive sunrises can be expressed as 1 day, as 24 h, as 1440 min or 86 400 s. We see that the numeric value changes depending on the unit of time, although it is always one and the same interval of time 5. Height of Mount Everest (h = 8.848 km) and the radius of the Earth (R = 6370 km) are obviously dimensional quantities, but their ratio, h/R = 0.0014, is dimensionless, and therefore, independent of the unit system 6. The dimension of volume of electric current is denoted by I, and the dimension of absolute temperature by .0143-0807/10/040893+14$30.00 c 2010 IOP Publishing Ltd Printed in the UK & the USA…”