You are presented with several wires made ofthe same conducting material. The radius and drift speed are givenfor each wire in terms of some unknown units \rm r and \rm v. Rank thewires in order of decreasing electron current.
Rank from most to least electroncurrent. To rank items as equivalent, overlap them.
radius=1 radius=4 radius =2 radius= 3
drift speed =5V drift speed = .5V drift speed = 2.5V drift speed = 1 V

The ranking of current from the most to the least is

Explanation:

Case Number  1 :

Drift velocity== 5v

Radius=r= 1r

Square of radius== 1

Current==C(5v)

Case Number 2 :

Drift velocity==0.5v

Radius=r=4r

Square of radius==16

Current== C(8v)

Case number 3 :

Drift velocity==2.5

Radius=r=2r

Square of radius==4

Current== C(10v)

Case number 4:

Drift velocity==1v

Radius=r=3r

Square of radius==9

Current==C(9v)

Hence, The ranking of current from the most to the least is

here we know that ball will drop down by total distance 3.2 m

so here we know that

now using kinematics

now in the same time it will cover horizontal distance of 0.75 m

so speed of the ball will be

unlike poles attract