Rate of decrease of velocity of an object moving with 6.25m//s is (dv)/(dr) =-2.5 sqrtv.Where v is instantaneous speed. Time taken by object to come to rest is .............

Rate of decrease of velocity of an object moving with 6.25m//s is (dv)

1.	Rate of decrease of velocity of an object moving with 6.25m//s is (dv)/(dr) =-2.5 sqrtv.Where v is instantaneous speed. Time taken by object to come to rest is .............
Answer» 1s 2s 4s 7s Solution :`(dv)/(dt)=- 2.5 sqrtv` `therefore (dv)/(sqrtv)=-2.5 dt` `therefore INT _(6.25 ) ^(0) (dv)/(sqrtv) =-2.5 int _(0) ^(t) dt` `therefore [-2 sqrtv]_(6.25) ^(0)=-2.5t` ` therefore -2 XX SQRT (6.25) =-2.5 t` `therefore -2 xx 2.5 =-2.5t` `therefore t =2` SECOND