Question

A 3.0kg block of wood is pushed along the horizontal flat surface with a force of 50.0 N. If the friction force is 10N, what is the acceleration of the box?

Answer 1

So what does the free body diagram for this look like? ^_^

Answer 2

\[ \sum F_y = N-mg=0
\\ \hspace{100px} N=mg\]
\[ \sum F_x = F_A - F_f = ma
\\ \
\\ \quad \quad F_A = 50N
\\ \quad \quad F_f = 10N
\\ \quad \quad m=3 \ kg\]
\[a= \frac{F_A - F_f}{m}\]