What would be the effect on the retarding force applied by the brakes if the length of the brakes is increased?

hi,

there would be no effect on retarding force which is nothing but a frictional force, as friction depends only on nature of material

not the area of contact........ 

Approved

See the force applied does not depend upon the length of the brakes, It depends only upon mass and acceleration of the vehicle.

Approved

Breaks work on the principle of friction. When we apply the breaks, it opposes the rotational motion of the wheel.

We know that,

Frictional Force = Coefficient of friction x Normal Reaction

Since, neither coefficient of friction or normal reaction, depend on the area of contact, hence there will be no effect if the length of the breaks are increased or decreased.

Please Approve!!

Approved