(Solved): A 6.170kg block of wood is at rest on a steel desk. The coefficient of static friction between th ...

A $6.170\mathrm{kg}$ block of wood is at rest on a steel desk. The coefficient of static friction between the block and the desk is ${?}_s=0.455$ and the coefficient of kinetic friction is ${?}_k=0.305$. At time $t=0$, Bob applies a force $\mathbf{F}=16.9\mathrm{N}\widehat{?}$ to the block. a) At time $t=0$, what is the value of the force of friction applied to the block? b) At time $t>0$, what is the value of the force of friction applied to the block? Bob sets up the experiment again, only this time, he applies a force of $\mathbf{F}=34.1\mathrm{N}\widehat{?}$. c) At time $t=0$, what is the value of the force of friction applied to the block?