Question

the free - body diagrams of four objects are shown. which object has a net force of - 5 n down? $f_n = 20n$, $f_f=-10n$, $f_p = 10n$, $f_g=-15n$ (for w) $f_n = 20n$, $f_f=-15n$, $f_p = 15n$, $f_g=-25n$ (for another w)

Explanation:

Step1: Define net - force in vertical direction

Net - force in vertical direction $F_{net - y}=F_N + F_g$, where $F_N$ is the normal force and $F_g$ is the gravitational force. Downward is considered negative.

Step2: Calculate net - force for object W

For object W, $F_N = 20N$ and $F_g=-25N$. Then $F_{net - y}=20+( - 25)=-5N$.

Answer:

W