Question

Do friction help in increasing the velocity of the object?

Answer 1

NO
Friction is directly proportional to the normal force of an object. Basically the speed of the object in the x direction does not effect the normal force in the y direction of an object to any discernable degree.

Remember F=U ×FN where U is the coefficent of kinetic friction and FN is normal force. So Friction does take into account a velocity, just not the velocity of the object in the x direction, the velocity friction uses is the velocity derived from the gravitational acceleration of an object in the y direction.

This should make intuitive sense, if you have an object you are pulling on the floor and you add mass or acceleration (by pushing down) you will notice it becomes harder to move(requires more force to over come higher friction force) at the same velocity. Also you may notice that an extremely heavy object can be "forced"in a direction without actually moving in that direction. This friction uses the coefficent of static friction and the force must be greater than this static friction to produce motion.

Think about it this way if you push on your refrigerator with the same force you push on a toaster, one will move while the other may not, this has nothing to do with the velocity of the object in the x direction but everything to do with the objects force in the y direction.