Nirmal Singh.
Last Activity: 11 Years ago
Consider two parallel wires separated by 1 m and carrying a current 1 A each then i1 = i2 =1 A and d = 1m so that from equation dF/ dl = miyu not i1*i2 / 2 pie d
dF/dl = 2 x 10^-7 N/m
This is used to formally define the unit ampere of electric current. if two parallel long wires kept 1 m apart in vacuum carry equal currents in the same direction and there is a force of attraction of 1x 10^-7 newton per meter of each wire, current in each wire is said to be 1 ampere.
Thanks & Regards,
Nirmal Singh
Askiitians Faculty