Question

1. what is the resultant force? a) 40 n b) 10 n c) 30 n d) 20 n 9. what is the resultant force? a) 0 n b) 90 n c) 30 n d) 60 n

Explanation:

Step1: Analyze forces in question 8

Forces are in opposite - direction. Take upward as positive and downward as negative. The forces are $F_1 = 10N$ (upward) and $F_2=30N$ (downward).
$F_{net}=F_1 - F_2$

Step2: Calculate net force for question 8

$F_{net}=10N-30N=- 20N$. The magnitude of the resultant force is $20N$.

Step3: Analyze forces in question 9

Forces are in the same - direction (downward). Let the two forces be $F_1 = 30N$ and $F_2 = 60N$.
$F_{net}=F_1 + F_2$

Step4: Calculate net force for question 9

$F_{net}=30N + 60N=90N$.

Answer:

1. d) 20 N
2. b) 90 N