Question

question 7 of 10
a box of mass 13 kg sits on a table with a coefficient of static friction of 0.85. what is the maximum force of static friction?
a. 98 n
b. 102 n
c. 127 n
d. 108 n

Explanation:

Step1: Calculate normal force

The normal force $N$ on a flat - surface is equal to the weight of the object, $N = mg$. Here, $m = 13\ kg$ and $g=9.8\ m/s^{2}$. So, $N=13\times9.8 = 127.4\ N$.

Step2: Calculate maximum static - friction force

The formula for the maximum static - friction force is $F_{s}=\mu_{s}N$, where $\mu_{s}=0.85$ and $N = 127.4\ N$. Then $F_{s}=0.85\times127.4=108.29\ N\approx108\ N$.

Answer:

D. 108 N