Question

It is the charge which when placed in vaccum at a distance of 1 meter from an equal and similar charges repel it with a force of 9×10^9N

Answer 1

1 Coulomb is the charge
because as we know
Electrostatic force = K q1.q2/D^2
when charge = 1 Coulomb
and distance = 1 m
F=K
in vacuum k=9×10^9Nm/C^2