1) a charged particle,having charge(+q),moves with constant speed (v) on a circular path of radius (r).the current corresponding to the motoin charged particle is..............?

2)a charged particle having charge (q) and mass (m) is given a velocity (v) in a uniform magnetic field (B) .the angle between (v) and (B) in 30^o.the radius of the helical path is...............? [assuming any other vector field to be absent]medical.entrancecorner.com/images/blank.png

i'm not too sure but I think the first one is something like this :

1)Current=nxq/T

T =2TTm/Bq

Just substitute and that gives the current.

T-Tme period,n-no. o electrons,q-charge

2)mv*2/r=Bqvsin30

mv*2/r=Bqv/2

2mv/Bq=r

sorry to say, but the answer for first one is qv/2πr

and second one is mv/2qB.................... bt i dnt knw how.

Yeah the second one is mv/2bq,sorry I made a mistake :|

But i'm not too sure about the first one either :(

The first one is like this :

I=charge/Time period

Time period =area(dist.)/velocity=2TTr/v

hence,

I=qv/2TTr