Question

what is friction? define static friction, limiting friction and kinetic friction​

Answer 1

$\bold{ \underline{Friction :-}}$

In our day to day life we use the word friction technically or practically.

▶Friction:- It is a force which oppose the motion or oppose the intension of motion.

❇ Friction is occurs at the point of contact.

❇ The direction of friction is common tangent.

❇ Friction is occur between the two surfaces.

❇ Friction adjust its value automatically and always oppose motion and intension of motion.

$\bold{ \underline{Static \: Friction :-}}$

❇When two objects having more relative motion between two bodies in contact is called Static friction.

❇Static friction doesn't exist by itself.

❇Static friction help us to start the motion or move.

❇For walking on ground or for starting a motion Static friction is necessary.

$\bold{ \underline{Limiting\: Friction:-}}$

❇ It is the maximum opposing force that comes into play, when one body is just at the verge of moving over the surface of the other body.

OR

It is the maximum value of static friction between surfaces of 2 object if applied force is increase beyond it to the object start, having realtive motion.

❇ To start a object or for starting a motion minimum limiting friction value must be applied.

❇The direction of force of limiting friction is always opposite to the direction in which body have intension to move.

$\bold{ \underline{Kinetic \: Friction:-}}$

❇ It is the opposing force that comes into play when one body is actually moving over the surface of another body.

In short:- If their is a realtive motion between bodies which is in contact is known as kinetic Friction.

❇ Kinetic Friction help us to stop the motion.

❇ Kinetic Friction is always slightly less than the limiting friction.

❇ Kinetic Friction is also known as dynamic friction.

Answer 2

Answer:

Friction:.

Opposing force exerted by the surface on the object which resist it's motion.

Static friction:

Force which opposes the initiation of motion of an object on the surface.

Kinetic friction:

External force acting on the object is greater than the maximum static friction, the object begins to slide.

When an object slided, the surface exerts a frictional force called kinetic friction.