The chains does not prevent the car wheels from sliding on the snow and give grip to the wheels

The chalk dust causes friction between the weightlifter’s hands and the bar so that his hands will slip

When you rub your hands together the friction does not causes anything

The people rub the ice to make it smoother so the rock will slide easily and so there will be no friction

Different ramps require different force as the slope and length of the ramp can make work easier or hard.

The wheel and axle has two basic parts: a large disc or wheel that is attached to a smaller cylinder or axle.

In a wheeled vehicle like your family car, the large wheel is the axle and the smaller cylinder is the tyre of the wheel.

the axle rotates to move the load

The teeth of the gear wheels are precisely cut so that each wheel interlinks with another smoothly.

The smaller gear is called the driving gear.

he larger gear is called the pinion.

The gear to which the force is directed is called the driven gear

Wheels with teeth that slot together

A grooved wheel with a chain or cable around it

An inclined plane wrapped around a shaft or cylinder

An object with at least one slanting side ending in the sharp edge

which simple machine is used here in this picture:

which simple machine in this picture:

which simple machine is used here :