Velocity of a particle moving in a curvilinear path in a horizontal $X$ $Y$ plane varies with time as $\vec v = (2t\hat i + t^2 \hat j) \ \  m/s.$ Here, $t$ is in second. At $t = 1\  s$

  • A

    acceleration of particle is $8\  m/s^2$

  • B

    tangential acceleration of particle is $\frac{4}{{\sqrt 5 }} \ m/s^2$

  • C

    radial acceleration of particle is $\frac{6}{{\sqrt 5 }} \ m/s^2$

  • D

    radius of curvature to the path is $\frac{5\sqrt 5}{{2 }} \ m$

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