Question

question 10 of 10
a tree limb of mass 12 kg falls straight down. if air resistance exerts 27 n of force on the limb as it falls, what is the net force on the tree limb?
a. 91 n down
b. 118 n down
c. 15 n down
d. 27 n down

Explanation:

Step1: Calculate gravitational force

The gravitational force $F_g = mg$, where $m = 12$ kg and $g= 9.8$ m/s². So $F_g=12\times9.8 = 117.6\approx118$ N (down - ward).

Step2: Calculate net force

The air - resistance $F_{air}=27$ N (up - ward). The net force $F_{net}=F_g - F_{air}$. Substitute the values: $F_{net}=118 - 27=91$ N (down - ward since the gravitational force is greater and acts downward).

Answer:

A. 91 N down