Question

If $ \mu_s $ and $ \mu_k $ are static and kinetic friction, then:

• A. \( \mu_s>\mu_k \) maximum value of \( \mu_s \)
• B. \( \mu_s \) is opposing impending motion
• C. \( \mu_s \) depends on area
• D. Both doesn’t depend on area

Hint:

Static friction is generally higher than kinetic friction, as it requires more force to overcome initial resistance between two objects than to keep them moving once in motion.

Answer 1

The Correct Option is A

The two types of friction in question are: - Static friction (\( \mu_s \)): This is the friction that resists the initiation of motion between two surfaces. Static friction has a maximum value, which is higher than the value of kinetic friction. It depends on the normal force between the surfaces, but it does not depend on the contact area between the surfaces, assuming the surfaces are uniform. 
- Kinetic friction (\( \mu_k \)): This is the friction that resists the motion of two surfaces sliding past each other. It is typically lower than static friction and is relatively constant once motion has started. 
Thus, the correct statement is that \( \mu_s>\mu_k \), and the maximum value of \( \mu_s \) is the threshold beyond which motion will occur. 
The answer is \( \mu_s>\mu_k \) maximum value of \(\mu_s\) .