[tex]\begin{gathered} \text{From the fre}e\text{ body diagram} \\ \uparrow+\Sigma Fy=0 \\ F_{norm}-F_{grav}=0 \\ F_{norm}=F_{grav} \\ F_{norm}=80N \\ \text{The normal force is 80N} \\ \\ F_{grav}=mg \\ \text{Solving m} \\ m=\frac{F_{grav}}{g} \\ m=\frac{\text{80N}}{9.81m/s^2} \\ m=8.15kg \\ The\text{ mass is }=8.15kg \\ \\ \rightarrow+\Sigma Fx=ma \\ F_{app}-F_{frict}=ma \\ 50N-10N=ma \\ 40N=ma \\ \text{Solving a} \\ a=\frac{40N}{m} \\ a=\frac{40N}{8.15kg} \\ a=4.9\text{ }m/s^2 \\ \text{The acceleration is }4.9\text{ }m/s^2 \end{gathered}[/tex]
