Which of the following is not a unit of energy
$W{\rm{ - s}}$
$kg{\rm{ - }}m/\sec $
$N{\rm{ - }}m$
Joule
Which of the following is not a unit of self-inductance
The unit of $e.m.f.$ is
The units of modulus of rigidity are
Unit of Stefan's constant is
The unit of permittivity of free space ${\varepsilon _0}$ is