Correct Answer - A
for translational motion `v = v_(0) + at`
`0 = v_(0) - (f)/(m) t rArr t = (mv_(0))/(f)`….(1)
for rotational motion
`omega = omega_(0) + alpha t`
`omega = omega_(0) + (tau)/(I) t`
`0 = omega_(0) - (Rf)/(I) t`
`t = (omega_(0) I)/(Rf)`
for disc `I = (1)/(2) MR^(2)`
`t = (1)/(2) (mR^(2). omega_(0))/(Rf) rArr t = (mR omega_(0))/(2 f)` ....(2)
from (1) & (2)
`(mv_(0))/(f) = (mR omega_(0))/(2 f) rArr (v_(0))/(R omega_(0)) = (1)/(2)`.
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