The displacement of a particle undergoing rectilinear motion along x-axis is given by X=2t​3+21t2+60t+6 where X is in meter And t is in second . find the acceleration of the particle when its velocity is zero ?

Given      X=2t3+21t2+60t+6So     dXdt=6t2+42t+60When velocity is zero then dXdt=0or      6t2+42t+60=0or        6t2+12t+30t+60=0or           6tt+2+30t+2=0or           t=-2s, -5sNow  differentiating the given eqn once again, we get;       d2Xdt2=12t+42So accelerations at time t=-2s and t=-5s is given by;             d2Xdt2=12×-2+42=-24+42=18m/s2and          d2Xdt2=12-5+42=-60+42=-18m/s2    

  • 6
What are you looking for?