A particle starts moving rectilinearly at time t = 0 such that its velocity v changes with time t according to the equation `v = t^2-t`, where t is in seconds and v is in `m s^(-1)`. The time interval for which the particle retrads (i.e., magnitude of velocity decreases)isA. `t lt 1//2`B. `1//2 ltt lt1`C. `tgt1`D. `tlt1//2 and tgt1`

A particle starts moving rectilinearly at time t = 0 such that its vel

1.	A particle starts moving rectilinearly at time t = 0 such that its velocity v changes with time t according to the equation `v = t^2-t`, where t is in seconds and v is in `m s^(-1)`. The time interval for which the particle retrads (i.e., magnitude of velocity decreases)isA. `t lt 1//2`B. `1//2 ltt lt1`C. `tgt1`D. `tlt1//2 and tgt1`
Answer» Correct Answer - B b. ` v= t^2-t rArr a = 9dv)/(dt) = 2t - 1 ` For retardation, `avlt0` `rArr (t^2-t)(2t-1)lt0` ` rArr t(t-1)(2t-1)lt0` This is possible for `1/2lttlt1`.

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