Question

1. what is the resultant/ net force? a) 400 n up b) - 400 n down c) 400 n down d) 800 n down

Explanation:

Step1: Define upward as positive

Let the upward - acting air force $F_{air}=200N$ and the downward - acting gravitational force $F_{gravity}=- 600N$.

Step2: Calculate net force

The net force $F_{net}$ is the sum of all forces. So, $F_{net}=F_{air}+F_{gravity}$. Substitute the values: $F_{net}=200+( - 600)=-400N$. The negative sign indicates the direction is downward.

Answer:

b) - 400 N Down