Question

what is the net force on this object? A. 22 newtons B. 8 newtons C. 0 newtons D. 36 newtons (there's a picture)

Answer 1

Watch in the diagram above that a downward vector will provide a partial or full cancellation of an upward vector. 

$F_{Net} = F_{Norm} - F_{grav}$
$F_{Net} = 20 - 20$
$F_{Net} = 0N$


And a leftward vector will provide a partial or full cancellation of a rightward vector.

In this case, as the meanings of the vectors are opposite, one of the forces receives the negative signal and thus a piece of the other vector is drawn, as shown in the figure. And to know the module of the resultant force, if it subtracts the modules of the forces.

$F_{Net} = F_{app} - F_{frict}$
$F_{Net} = 22 - 14$
$\boxed{\boxed{F_{Net} = 8N}}$

Answer:

(in order to have a net force of 8 N, right) 

B. 8 Newtons