Answer:
F = 100 N
Step-by-step explanation:
The torque is given by the expression
τ = F x r
where bold letters indicate vectors, the magnitude of this expression is
τ = F r sin θ
In general, when tightening a nut, the force is applied perpendicular to the arm, therefore θ = 90 and sin 90 = 1
τ = F r
F = τ / r
calculate
F = 30 / 0.30
F = 100 N