purifier said:
It is a known fact that time constant of a series circuit is RC that is ohm*farad... But how come the units are seconds? Similarly we also have T=L/R Henry/Ohm...even then the units are seconds... Can someone tell me how the units are arrived at? Please help....
All things are calculated in SI units, and if you check a website about SI units, you can find how all units are derived. There are 7 SI base unites and all other SI units are derived from these and can be expressed in terms of SI base units
Check this site for example:
https://physics.nist.gov/cuu/Units/units.html
The 7 SI base units:
Code:
Base quantity Name Symbol
length meter m
mass kilogram kg
time second s
electric current ampere A
thermodynamic temperature kelvin K
amount of substance mole mol
luminous intensity candela cd
Expression in terms of SI base units:
Electrical resitance, R (ohm) [Ω]: m^2 · kg · s^-3 · A^-2
Capacitance, C (farad) [F]: m^-2 · kg^-1 · s^4 · A^2
Inductance, L (henry) [H]: m^2 · kg · s^-2 · A^-2
If you multiply the two SI units for R and C, you will end up with the SI unit seconds:
R·C: (m^2 · kg · s^-3 · A^-2) · (m^-2 · kg^-1 · s^4 · A^2) =
s
If you devide the SI unit for L with the SI unit for R, you will also end up with the SI unit seconds:
L/R: (m^2 · kg · s^-2 · A^-2) / (m^2 · kg · s^-3 · A^-2) =
s
Whenever you are in doubt which unit you will end up with when you multiply, divide, add or subtract more units, just check the SI units and you will know which unit you will end up with.