Answer:
16.935 N
Explanation:
In order to make the box start moving, the level force applied on the box (F) must be greater than the force of static friction that keeps the box at rest, which is equal to
[tex]F_f = \mu_s (mg)[/tex]
where
[tex]\mu_s = 0.5645[/tex] is the coefficient of static friction
(mg) = 30 N is the weight of the box
Therefore, the condition for F must be:
[tex]F \geq F_f\\F \geq \mu_k (mg)=(0.5645)(30 N)=16.935 N[/tex]
So, the applied force must be greater than this value.