1. With N = Newtons, m = meters, we have
N itself can be broken down according to Newton's second law,
so the dimension of the force
is
(where M = mass, L = length, T = time) and hence the dimension of
is
2.
a. With N = Newtons, A = amperes, and m = meters,
b. The dimension of
is
(where I = current, with "I" as in capital i)