Smrita is climbing a mountain. How much friction does she need?

Jack is going skiing. How much friction does he need?

How does friction affect speed?

Friction is the force opposing one solid object's movement over another. Four categories of friction exist fluid friction, rolling friction, sliding friction, and static friction.
¶The frictional force keeps our feet planted on the ground when we walk on or on the floor. As a result, we frequently slip on icy or slippery surfaces because there is less friction.
¶According to scientists, friction is caused by the interactions of tiny bumps on surfaces as they rub against each other. The bumps on each surface bend and exert force on each other, making it difficult for the surfaces to slip over each other.

A smooth surface has ____.

A marble floor offers less friction. Which property is being related with friction?

Friction does not depend upon the ____.

Friction depends on the ____.

Whenever the surfaces in contact tend to move with respect to each other, the force of friction comes into play 

Friction can be reduced by using

Friction always ____ of an object.

Friction is a ____.

The force of friction always acts in the direction __________ to that of the applied force.

The speed of an object _______ due to the frictional force.

The force of friction always acts in the direction _____ to which an object moves or tries to move.

The unit to measure friction is ____.

The force that opposes or resists the relative motion between the two surfaces of objects in contact is called ____.