Question Detail
Question
For the same 10 kg block (μ_s=0.4, μ_k=0.3), once it is sliding, what is the kinetic friction force?
Correct Answer
Option B is the correct answer.
Detailed Explanation
The normal force F_N is still 100 N. The kinetic friction force f_k = μ_k F_N = 0.3 * 100 N = 30 N.
Hint
Use the formula for kinetic friction, f_k = μ_k F_N.