Question

What are Static and Sliding friction?

Answer 1

Hint: Static and sliding are two different types of friction. Static itself represents the state of rest while sliding represents the state of motion. Both work between the surface of two bodies and create a frictional force on the surface.


Complete step by step solution:
Static Friction:
It is the force which acts between two bodies when a force is applied on a body but there is no relative motion between surfaces of the body. It always opposes impending motion.
Law of Static Friction is given by,
${f_s} \leqslant {\mu _s}N$
Where,
${\mu _s} - $ Coefficient of statics friction
${f_s} - $ Static Friction
$N - $ Normal Force
Coefficient of static friction depends on material used or on the surface of the body. Range of coefficients of friction varies from zero to greater than one.
Sliding Friction:
It is the force which comes into play when the surface of one object moves relative to the surface of another object. It is the force which keeps a surface sliding with another surface. This friction acts between two surfaces that are rubbing against each other.
Hence,
${f_k} = {\mu _k}N$

Additional Information:
Types of Frictional Force:
- Static Friction
- Sliding Friction
- Rolling Friction
- Fluid Friction

Note:
Keep in mind both the friction is different from each other. Remember that if a body is placed over a surface then it will experience a normal force acting on it and the direction of normal force is generally opposite to force due to gravity and is perpendicular to the surface of the body.