Answer:
[tex]\mu_k=\frac{a}{g}[/tex]
Explanation:
The force of kinetic friction on the block is defined as:
[tex]F_k=\mu_kN[/tex]
Where [tex]\mu_k[/tex] is the coefficient of kinetic friction between the block and the surface and N is the normal force, which is always perpendicular to the surface that the object contacts. So, according to the free body diagram of the block, we have:
[tex]N=mg\\F_k=F=ma[/tex]
Replacing this in the first equation and solving for [tex]\mu_k[/tex]:
[tex]ma=\mu_k(mg)\\\mu_k=\frac{a}{g}[/tex]
