Question

The limiting value of static friction between two contact surfaces is :

• A. Proportional to normal force between the surfaces in contact.
• B. Independent of area of contact
• C. Depends on the microscopic area of constant magnitude.
• D. All of the above

Answer 1

The correct option is A Proportional to normal force between the surfaces in contact.

The limiting value of the static friction between the two contact surfaces is calculated by the product of the applied force and the normal force as shown in the formula below:

$F={\mu }_{s}N$

The friction depends only on the frictional coefficient of the material and if we increase the area of the contact between the surface then the source of the frictional force also get extended.