Question Detail
Question
If the normal force on an object sliding on a surface is doubled, what happens to the kinetic friction force?
Correct Answer
Option C is the correct answer.
Detailed Explanation
The kinetic friction force is given by f_k = μ_k F_N. If μ_k is constant and F_N doubles, then f_k will also double.
Hint
Look at the formula f_k = μ_k F_N. Friction is directly proportional to the normal force.